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Less common in cavities of sedimentary and plutonic rocks.","The name is derived from its occurrence at the Achates River in southwestern Sicily.",0,"2026-01-01 18:17:13",{"id":11,"name":42,"entrytype":9,"csystem":8,"ima_formula":8,"mindat_formula":14,"hmin":20,"hmax":21,"dmeas":22,"dcalc":19,"strunz10ed1":19,"primary_image_id":43},"Chalcedony",87926,[45,49,53,58,62,66,69,73,77,81,84,88,92,96,100,104,107,111],{"id":46,"name":47,"entrytype":9,"csystem":8,"ima_formula":8,"mindat_formula":14,"hmin":8,"hmax":8,"dmeas":19,"dcalc":8,"primary_image_id":48},52,"Agate-Jasper",87529,{"id":50,"name":51,"entrytype":9,"csystem":8,"ima_formula":8,"mindat_formula":14,"hmin":8,"hmax":8,"dmeas":8,"dcalc":8,"primary_image_id":52},43510,"Agatized coral",31614,{"id":54,"name":55,"entrytype":9,"csystem":56,"ima_formula":8,"mindat_formula":14,"hmin":21,"hmax":21,"dmeas":19,"dcalc":8,"primary_image_id":57},699,"Blue Lace 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Agate",63537,{"id":97,"name":98,"entrytype":9,"csystem":8,"ima_formula":8,"mindat_formula":14,"hmin":8,"hmax":8,"dmeas":19,"dcalc":8,"primary_image_id":99},7613,"Mexican Lace Agate",67398,{"id":101,"name":102,"entrytype":9,"csystem":56,"ima_formula":8,"mindat_formula":14,"hmin":20,"hmax":21,"dmeas":22,"dcalc":19,"primary_image_id":103},2999,"Onyx",71446,{"id":105,"name":106,"entrytype":9,"csystem":8,"ima_formula":8,"mindat_formula":14,"hmin":8,"hmax":8,"dmeas":19,"dcalc":19,"primary_image_id":8},27173,"Pigeon Blood Agate",{"id":108,"name":109,"entrytype":9,"csystem":8,"ima_formula":8,"mindat_formula":14,"hmin":8,"hmax":8,"dmeas":19,"dcalc":8,"primary_image_id":110},7604,"Sardonyx",71450,{"id":112,"name":113,"entrytype":9,"csystem":8,"ima_formula":8,"mindat_formula":14,"hmin":8,"hmax":8,"dmeas":8,"dcalc":8,"primary_image_id":8},39865,"Youngite",[],[116,125,136,144],{"id":117,"name":118,"entrytype":39,"csystem":56,"ima_formula":119,"mindat_formula":120,"hmin":121,"hmax":121,"dmeas":122,"dcalc":123,"primary_image_id":124},859,"Calcite","Ca(CO\u003Csub>3\u003C\u002Fsub>)","CaCO\u003Csub>3\u003C\u002Fsub>",3,"2.7102","2.711",4401,{"id":126,"name":127,"entrytype":39,"csystem":128,"ima_formula":129,"mindat_formula":130,"hmin":131,"hmax":132,"dmeas":133,"dcalc":134,"primary_image_id":135},1719,"Goethite","Orthorhombic","FeO(OH)","Fe\u003Csup>3+\u003C\u002Fsup>O(OH)",5,5.5,"4.27","4.18",29787,{"id":137,"name":138,"entrytype":39,"csystem":56,"ima_formula":139,"mindat_formula":139,"hmin":131,"hmax":140,"dmeas":141,"dcalc":142,"primary_image_id":143},1856,"Hematite","Fe\u003Csub>2\u003C\u002Fsub>O\u003Csub>3\u003C\u002Fsub>",6,"5.26","5.255",29858,{"id":145,"name":146,"entrytype":39,"csystem":56,"ima_formula":14,"mindat_formula":14,"hmin":21,"hmax":21,"dmeas":147,"dcalc":148,"primary_image_id":149},3337,"Quartz","2.65","2.66",30579,[],[],1192,[154,157,161,165,170,174,179,183,187,191,195,198,202,207,211,214,217,220,224,227,230,233,238,242,247,251,255,259,264,268,273,277,280,284,288,293,298,303,308,313,317,322,326,330,335,339,344,349],{"id":155,"year":8,"html":156,"doi":8},16099552,"http:\u002F\u002Fwww.achat-almanach.de [in English and German]",{"id":158,"year":159,"html":160,"doi":8},17602548,1892,"Lévy, Auguste Michel, Munier-Chalmas, Ernest (1892) Mémoire sur diverses formes affectées par le réseau élémentaire du quartz. \u003Ci>Bulletin de la Société française de Minéralogie\u003C\u002Fi>,  15 (7). 159-190",{"id":162,"year":163,"html":164,"doi":8},16099518,1927,"Bernauer, F. (1927) Über Zickzackbänderung (Runzelbänderung) und verwandte Polarisationserscheinungen an Kristallen und Kristallaggregaten. Neues Jahrbuch für Mineralogie, Geologie und Paläontologie, Beilageband: 55: 92-143.",{"id":166,"year":167,"html":168,"doi":169},104778,1933,"Correns, Carl W.; Nagelschmidt, Günter (1933) Über Faserbau und optische Eigenschaften von Chalzedon. \u003Ci>Zeitschrift für Kristallographie\u003C\u002Fi>,  85 (1-6). 199-213 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1524\u002Fzkri.1933.85.1.199'>doi:10.1524\u002Fzkri.1933.85.1.199\u003C\u002Fa>","10.1524\u002Fzkri.1933.85.1.199",{"id":171,"year":172,"html":173,"doi":8},522256,1952,"Jones, Francis T. (1952) Iris agate. \u003Ci>American Mineralogist\u003C\u002Fi>,  37 (7-8) 578-587 \u003Ca target='_blank' href='http:\u002F\u002Fwww.minsocam.org\u002Fammin\u002FAM37\u002FAM37_578.pdf' class='refpdflink'>\u003C\u002Fa>",{"id":175,"year":176,"html":177,"doi":178},7745473,1956,"Braitsch, Otto (1956) Über die natürlichen Faser- und Aggregationstypen beim SiO2, ihre Verwachsungsformen, Richtungsstatistik und Doppelbrechung. \u003Ci>Heidelberger Beiträge zur Mineralogie und Petrographie\u003C\u002Fi>,  5 (4) 331-372 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1007\u002Fbf01115659'>doi:10.1007\u002Fbf01115659\u003C\u002Fa>","10.1007\u002Fbf01115659",{"id":180,"year":181,"html":182,"doi":8},524030,1964,"Monroe, E. A. (1964) Electron optical observations of fine-grained silica minerals. \u003Ci>American Mineralogist\u003C\u002Fi>,  49 (3-4) 339-347 \u003Ca target='_blank' href='http:\u002F\u002Fwww.minsocam.org\u002Fammin\u002FAM49\u002FAM49_339.pdf' class='refpdflink'>\u003C\u002Fa>",{"id":184,"year":185,"html":186,"doi":8},526977,1978,"Frondel, Clifford (1978) Characters of quartz fibers. \u003Ci>American Mineralogist\u003C\u002Fi>,  63 (1-2) 17-27 \u003Ca target='_blank' href='http:\u002F\u002Fwww.minsocam.org\u002Fammin\u002FAM63\u002FAM63_17.pdf' class='refpdflink'>\u003C\u002Fa>",{"id":188,"year":189,"html":190,"doi":8},16099524,1982,"Frondel, C. (1982) Structural hydroxyl in chalcedony (type B quartz). American Mineralogist: 67: 1248-1257.",{"id":192,"year":193,"html":194,"doi":8},528155,1985,"Frondel, Clifford (1985) Systematic compositional zoning in the quartz fibers of agates. \u003Ci>American Mineralogist\u003C\u002Fi>,  70 (9-10) 975-979 \u003Ca target='_blank' href='http:\u002F\u002Fwww.minsocam.org\u002Fammin\u002FAM70\u002FAM70_975.pdf' class='refpdflink'>\u003C\u002Fa>",{"id":196,"year":193,"html":197,"doi":8},16099525,"Fallick, A.E., Jocelyn, J., Donelly, T., Guy, M., Behan, C. (1985) Origin of agates in volcanic rocks from Scotland. Nature: 313: 672-674.",{"id":199,"year":200,"html":201,"doi":8},16099527,1991,"Flörke, O.W., Graetsch, H., Martin, B., Röller, K., Wirth, R. (1991) Nomenclature of micro- and non-crystalline silica minerals based on structure and microstructure. Neues Jahrbuch für Mineralogie - Abhandlungen: 163: 19-42.",{"id":203,"year":204,"html":205,"doi":206},2421815,1992,"HEANEY, P. J., POST, J. E. (1992) The Widespread Distribution of a Novel Silica Polymorph in Microcrystalline Quartz Varieties. \u003Ci>Science\u003C\u002Fi>, 255 (5043). 441-443 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1126\u002Fscience.255.5043.441'>doi:10.1126\u002Fscience.255.5043.441\u003C\u002Fa>","10.1126\u002Fscience.255.5043.441",{"id":208,"year":209,"html":210,"doi":8},529640,1994,"Heaney, Peter J., Veblen, David R., Post, Jeffrey E. (1994) Structural disparities between chalcedony and macrocrystalline quartz. \u003Ci>American Mineralogist\u003C\u002Fi>,  79 (5-6) 452-460 \u003Ca target='_blank' href='http:\u002F\u002Fwww.minsocam.org\u002Fammin\u002FAM79\u002FAM79_452.pdf' class='refpdflink'>\u003C\u002Fa>",{"id":212,"year":209,"html":213,"doi":8},16099531,"Lu, T. Sunagawa, I. (1994) Texture formation of agate in geode. Mineralogical Journal: 17: 53-76.",{"id":215,"year":209,"html":216,"doi":8},16099532,"Tanaka, T., Kamioka, H. (1994) Trace element abundance in agate. Geochemical Journal: 28: 359-362.",{"id":218,"year":209,"html":219,"doi":8},16121337,"Graetsch, H. (1994) Structural characteristics of opaline and microcrystalline silica minerals. in: Heaney, P.J., Gibbs, G.V., editors. Reviews in Mineralogy Volume 29 Silica - Physical behaviour, geochemistry and materials applications. Mineralogical Society of America, 209-232.",{"id":221,"year":222,"html":223,"doi":8},16099533,1995,"Taijing, L., Zhang, X. (1995) Nanometer scale textures in agate and Beltane opal. Mineralogical Magazine: 59: 103-109.",{"id":225,"year":222,"html":226,"doi":8},16099534,"Heaney, P.J., Davis, A.M. (1995) Observation and origin of self-organized textures in agates. Science: 269: 1562-1565.",{"id":228,"year":222,"html":229,"doi":8},16099535,"Merino, E., Wang, Y., Deloule, E. (1995) Genesis of agates in flood basalts: twisting of chalcedony fibers and trace-element geochemistry. American Journal of Science: 295: 1156-1176.",{"id":231,"year":222,"html":232,"doi":8},16099536,"Wang, Y., Merino, E. (1995) Origin of fibrosity and banding in agates from flood basalts. American Journal of Science: 295: 49-77.",{"id":234,"year":235,"html":236,"doi":237},77608,1998,"Cady, S. L., Wenk, H.-R., Sintubin, M. (1998) Microfibrous quartz varieties: characterization by quantitative X-ray texture analysis and transmission electron microscopy. \u003Ci>Contributions to Mineralogy and Petrology\u003C\u002Fi>,  130 (3) 320-335 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1007\u002Fs004100050368'>doi:10.1007\u002Fs004100050368\u003C\u002Fa>","10.1007\u002Fs004100050368",{"id":239,"year":235,"html":240,"doi":241},77691,"Götze, Jens, Nasdala, Lutz, Kleeberg, Reinhard, Wenzel, Marita (1998) Occurrence and distribution of “moganite” in agate\u002Fchalcedony: a combined micro-Raman, Rietveld, and cathodoluminescence study. \u003Ci>Contributions to Mineralogy and Petrology\u003C\u002Fi>,  133 (1) 96-105 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1007\u002Fs004100050440'>doi:10.1007\u002Fs004100050440\u003C\u002Fa>","10.1007\u002Fs004100050440",{"id":243,"year":244,"html":245,"doi":246},1270,1999,"Götze, J., Plötze, M., Fuchs, H., Habermann, D. (1999) Defect structure and luminescence behaviour of agate — results of electron paramagnetic resonance (EPR) and cathodoluminescence (CL) studies. \u003Ci>Mineralogical Magazine\u003C\u002Fi>,  63 (2) 149-163 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1180\u002F002646199548394'>doi:10.1180\u002F002646199548394\u003C\u002Fa> \u003Ca target='_blank' href='https:\u002F\u002Frruff.info\u002Fdoclib\u002FMinMag\u002FVolume_63\u002F63-2-149.pdf' class='refpdflink'>\u003C\u002Fa>","10.1180\u002F002646199548394",{"id":248,"year":249,"html":250,"doi":8},16099539,2000,"Weise, C., publisher (2000) Achat - extraLapis Nr.19. Christian Weise Verlag, München.",{"id":252,"year":253,"html":254,"doi":8},16099540,2002,"Carlson, M.R. (2002) The Beauty of Banded Agates. Edina: Fortification Press.",{"id":256,"year":253,"html":257,"doi":258},128174,"Moxon, Terry (2002) Agate: a study of ageing. \u003Ci>European Journal of Mineralogy\u003C\u002Fi>,  14 (6) 1109-1118 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1127\u002F0935-1221\u002F2002\u002F0014-1109'>doi:10.1127\u002F0935-1221\u002F2002\u002F0014-1109\u003C\u002Fa>","10.1127\u002F0935-1221\u002F2002\u002F0014-1109",{"id":260,"year":261,"html":262,"doi":263},128333,2004,"Moxon, Terry, Rí os, Susana (2004) Moganite and water content as a function of age in agate: an XRD and thermogravimetric study. \u003Ci>European Journal of Mineralogy\u003C\u002Fi>,  16 (2) 269-278 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1127\u002F0935-1221\u002F2004\u002F0016-0269'>doi:10.1127\u002F0935-1221\u002F2004\u002F0016-0269\u003C\u002Fa>","10.1127\u002F0935-1221\u002F2004\u002F0016-0269",{"id":265,"year":266,"html":267,"doi":8},16099543,2005,"Zenz, J. (2005) Achate. Bode Verlag, 656 pp. (in German).",{"id":269,"year":270,"html":271,"doi":272},243718,2006,"Moxon, T., Reed, S. J. B. (2006) Agate and chalcedony from igneous and sedimentary hosts aged from 13 to 3480 Ma: a cathodoluminescence study. \u003Ci>Mineralogical Magazine\u003C\u002Fi>,  70 (5) 485-498 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1180\u002F0026461067050347'>doi:10.1180\u002F0026461067050347\u003C\u002Fa>","10.1180\u002F0026461067050347",{"id":274,"year":275,"html":276,"doi":8},16099545,2009,"Zenz, J. (2009) Achate II. Bode Verlag, 656 pp. (in German).",{"id":278,"year":275,"html":279,"doi":8},16099547,"Moxon, T. (2009): Studies on Agate: Microscopy, Spectroscopy, Growth, High Temperature and Possible Origin. Terra Publications, Doncaster, UK, 96 pp.",{"id":281,"year":275,"html":282,"doi":283},16990404,"Moxon, T.; Carpenter, M. A. (2009) Crystallite growth kinetics in nanocrystalline quartz (agate and     chalcedony). \u003Ci>Mineralogical Magazine\u003C\u002Fi>,  73 (4). 551-568 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1180\u002Fminmag.2009.073.4.551'>doi:10.1180\u002Fminmag.2009.073.4.551\u003C\u002Fa>","10.1180\u002Fminmag.2009.073.4.551",{"id":285,"year":286,"html":287,"doi":8},16099548,2010,"Weise, C., publisher (2010) Achate - geboren aus Vulkanen. extraLapis Nr.39. Christian Weise Verlag, München, 98pp.",{"id":289,"year":290,"html":291,"doi":292},244679,2015,"Götze, Jens, Gaft, Michael, Möckel, Robert (2015) Uranium and uranyl luminescence in agate\u002Fchalcedony. \u003Ci>Mineralogical Magazine\u003C\u002Fi>,  79 (4) 985-995 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1180\u002Fminmag.2015.079.4.08'>doi:10.1180\u002Fminmag.2015.079.4.08\u003C\u002Fa>","10.1180\u002Fminmag.2015.079.4.08",{"id":294,"year":295,"html":296,"doi":297},244948,2017,"Moxon, Terry (2017) A re-examination of water in agate and its bearing on the agate genesis enigma. \u003Ci>Mineralogical Magazine\u003C\u002Fi>,  81 (5) 1223-1244 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1180\u002Fminmag.2017.081.002'>doi:10.1180\u002Fminmag.2017.081.002\u003C\u002Fa>","10.1180\u002Fminmag.2017.081.002",{"id":299,"year":300,"html":301,"doi":302},7735075,2018,"Richter-Feig, Julia, Möckel, Robert, Götze, Jens, Heide, Gerhard (2018) Investigation of Fluids in Macrocrystalline and Microcrystalline Quartz in Agate Using Thermogravimetry-Mass-Spectrometry. \u003Ci>Minerals\u003C\u002Fi>, 8 (2) 72 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.3390\u002Fmin8020072'>doi:10.3390\u002Fmin8020072\u003C\u002Fa> \u003Ca target='_blank' href='https:\u002F\u002Fwww.mdpi.com\u002F2075-163X\u002F8\u002F2\u002F72\u002Fpdf?version=1519444390' class='refpdflink'>\u003C\u002Fa>","10.3390\u002Fmin8020072",{"id":304,"year":305,"html":306,"doi":307},245129,2019,"Götze, Jens, Berek, Harry, Schäfer, Klaus (2019) Micro-structural phenomena in agate\u002Fchalcedony: spiral growth. \u003Ci>Mineralogical Magazine\u003C\u002Fi>,  83 (2) 281-291 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1180\u002Fmgm.2018.156'>doi:10.1180\u002Fmgm.2018.156\u003C\u002Fa>","10.1180\u002Fmgm.2018.156",{"id":309,"year":310,"html":311,"doi":312},13422861,2020,"Moxon, Terry; Palyanova, Galina (2020) Agate Genesis: A Continuing Enigma. \u003Ci>Minerals\u003C\u002Fi>,  10 (11). 953 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.3390\u002Fmin10110953'>doi:10.3390\u002Fmin10110953\u003C\u002Fa> \u003Ca target='_blank' href='https:\u002F\u002Fwww.mdpi.com\u002F2075-163X\u002F10\u002F11\u002F953\u002Fpdf?version=1605757118' class='refpdflink'>\u003C\u002Fa>","10.3390\u002Fmin10110953",{"id":314,"year":310,"html":315,"doi":316},13422778,"Götze, Jens, Möckel, Robert, Pan, Yuanming (2020) Mineralogy, Geochemistry and Genesis of Agate—A Review. \u003Ci>Minerals\u003C\u002Fi>, 10 (11) 1037 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.3390\u002Fmin10111037'>doi:10.3390\u002Fmin10111037\u003C\u002Fa> \u003Ca target='_blank' href='https:\u002F\u002Fwww.mdpi.com\u002F2075-163X\u002F10\u002F11\u002F1037\u002Fpdf?version=1606103805' class='refpdflink'>\u003C\u002Fa>","10.3390\u002Fmin10111037",{"id":318,"year":319,"html":320,"doi":321},13421785,2021,"Zhou, Danyi, Shi, Guanghai, Liu, Suzhen, Wu, Bailing (2021) Mineralogy and Magnetic Behavior of Yellow to Red Xuanhua-Type Agate and Its Indication to the Forming Condition. \u003Ci>Minerals\u003C\u002Fi>, 11 (8) 877 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.3390\u002Fmin11080877'>doi:10.3390\u002Fmin11080877\u003C\u002Fa> \u003Ca target='_blank' href='https:\u002F\u002Fwww.mdpi.com\u002F2075-163X\u002F11\u002F8\u002F877\u002Fpdf?version=1629864208' class='refpdflink'>\u003C\u002Fa>","10.3390\u002Fmin11080877",{"id":323,"year":319,"html":324,"doi":325},13421624,"Palyanova, Galina (2021) Editorial for Special Issue “Agates: Types, Mineralogy, Deposits, Host Rocks, Ages and Genesis”. \u003Ci>Minerals\u003C\u002Fi>, 11 (10) 1035 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.3390\u002Fmin11101035'>doi:10.3390\u002Fmin11101035\u003C\u002Fa> \u003Ca target='_blank' href='https:\u002F\u002Fwww.mdpi.com\u002F2075-163X\u002F11\u002F10\u002F1035\u002Fpdf?version=1632713772' class='refpdflink'>\u003C\u002Fa>","10.3390\u002Fmin11101035",{"id":327,"year":319,"html":328,"doi":329},15724213,"Palyanova, Galina - \u003Ci>Ed.\u003C\u002Fi> (2021) \u003Ci>Agates: Types, Mineralogy, Deposits, Host Rocks, Ages and Genesis\u003C\u002Fi>. MDPI. \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.3390\u002Fbooks978-3-0365-2184-8'>doi:10.3390\u002Fbooks978-3-0365-2184-8\u003C\u002Fa> \u003Ca target='_blank' href='https:\u002F\u002Fmdpi-res.com\u002Fbookfiles\u002Fbook\u002F4444\u002FAgates_Types_Mineralogy_Deposits_Host_Rocks_Ages_and_Genesis.pdf' class='refpdflink'>\u003C\u002Fa>","10.3390\u002Fbooks978-3-0365-2184-8",{"id":331,"year":332,"html":333,"doi":334},14947581,2022,"Lorenzi, Roberto; Zullino, Andrea; Gagliardi, Valentina; Prosperi, Loredana; Paleari, Alberto; Adamo, Ilaria (2022) Atomic and microstructural origin of banded colours in purple-blue variety of agate from Yozgat Province, Turkey. \u003Ci>Physics and Chemistry of Minerals\u003C\u002Fi>,  49 (8). 33 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1007\u002Fs00269-022-01208-3'>doi:10.1007\u002Fs00269-022-01208-3\u003C\u002Fa>","10.1007\u002Fs00269-022-01208-3",{"id":336,"year":332,"html":337,"doi":338},15373944,"Conte, Alessandra; Della Ventura, Giancarlo; Rondeau, Benjamin; Romani, Martina; Cestelli Guidi, Mariangela; La, Carole; Napoleoni, Camilla; Lucci, Federico (2022) Hydrothermal genesis and growth of the banded agates from the Allumiere-Tolfa volcanic district (Latium, Italy). \u003Ci>Physics and Chemistry of Minerals\u003C\u002Fi>,  49 (10). 39 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1007\u002Fs00269-022-01214-5'>doi:10.1007\u002Fs00269-022-01214-5\u003C\u002Fa>","10.1007\u002Fs00269-022-01214-5",{"id":340,"year":341,"html":342,"doi":343},15841010,2023,"Mrozik, Maximilian, Götze, Jens, Pan, Yuanming, Möckel, Robert (2023) Mineralogy, Geochemistry, and Genesis of Agates from Chihuahua, Northern Mexico. \u003Ci>Minerals\u003C\u002Fi>, 13 (5) 687 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.3390\u002Fmin13050687'>doi:10.3390\u002Fmin13050687\u003C\u002Fa>","10.3390\u002Fmin13050687",{"id":345,"year":346,"html":347,"doi":348},17161569,2024,"Papineau, Dominic (2024) Chemically Oscillating Reactions as a New Model for the Formation of Mineral Patterns in Agate Geodes and Concretions. \u003Ci>Minerals\u003C\u002Fi>,  14 (2)  \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.3390\u002Fmin14020203'>doi:10.3390\u002Fmin14020203\u003C\u002Fa>","10.3390\u002Fmin14020203",{"id":350,"year":351,"html":352,"doi":353},17823314,2025,"Zhang, Peng, Wang, Bo-Chao, Huang, Xiao-Wen, Xi, Xi (2025) Geochemical Discrimination of Agate in Diverse Volcanic Host Rocks Through Machine Learning Methods. \u003Ci>Minerals\u003C\u002Fi>,  15 (1).  \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.3390\u002Fmin15010032'>doi:10.3390\u002Fmin15010032\u003C\u002Fa>","10.3390\u002Fmin15010032",[355,362,367,377,382,391,396,401,411,419,428,437,444,450,457,465,473,480,487,496,503,513,523,530,537,544,551,559,568,575,582,589,598,605,612,618,625,633,643,651,658,665,673,681,688,695,701,708,716,724,732,740,747,754,760,768,777,785,794,802,808,817,826,835,844,851,860,867,874,882,889,896,904,912,920,929,938,946,954,961,967,974,981,987,993,1000,1007,1016,1023,1029,1036,1044,1052,1057,1062,1068,1077,1085,1093,1100,1107,1116,1124,1133,1142,1151,1160,1166,1174,1183,1192,1201,1206,1215,1223,1229,1237,1246,1255,1262,1270,1278,1286,1294,1300],{"id":356,"source_url":357,"license_code":358,"credit_html":359,"title":7,"description":8,"author":8,"original_width":360,"original_height":361},87523,"https:\u002F\u002Fgeocollections.info\u002Ffile\u002F93080","CC BY-SA 4.0","Photo: Unknown author — http:\u002F\u002Fcreativecommons.org\u002Flicenses\u002Fby-sa\u002F4.0\u002F, courtesy of \u003Ca href=\"https:\u002F\u002Fgeocollections.info\u002Ffile\u002F93080\" rel=\"noopener\">The Estonian Museum of Natural History\u003C\u002Fa> via Europeana",1000,601,{"id":363,"source_url":364,"license_code":358,"credit_html":365,"title":7,"description":8,"author":8,"original_width":360,"original_height":366},87525,"https:\u002F\u002Fgeocollections.info\u002Ffile\u002F93057","Photo: Unknown author — http:\u002F\u002Fcreativecommons.org\u002Flicenses\u002Fby-sa\u002F4.0\u002F, courtesy of \u003Ca href=\"https:\u002F\u002Fgeocollections.info\u002Ffile\u002F93057\" rel=\"noopener\">The Estonian Museum of Natural History\u003C\u002Fa> via Europeana",721,{"id":368,"source_url":369,"license_code":370,"credit_html":371,"title":372,"description":373,"author":374,"original_width":375,"original_height":376},31545,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=84847540","CC BY 4.0","Photo3.0 (Gianluca Nicoli), via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=84847540\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Microscopio 00028 Agata Metodo Media Ponderata (B).jpg","Agata, Nikon D3000, polarized optical microscope, focus stacking image","Photo3.0 (Gianluca Nicoli)",3872,2286,{"id":378,"source_url":379,"license_code":358,"credit_html":380,"title":7,"description":8,"author":8,"original_width":360,"original_height":381},87526,"https:\u002F\u002Fgeocollections.info\u002Ffile\u002F94567","Photo: Unknown author — http:\u002F\u002Fcreativecommons.org\u002Flicenses\u002Fby-sa\u002F4.0\u002F, courtesy of \u003Ca href=\"https:\u002F\u002Fgeocollections.info\u002Ffile\u002F94567\" rel=\"noopener\">The Estonian Museum of Natural History\u003C\u002Fa> via Europeana",928,{"id":383,"source_url":384,"license_code":358,"credit_html":385,"title":386,"description":387,"author":388,"original_width":389,"original_height":390},31546,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=95195514","Zeyklc SAU20, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=95195514\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agat Taşı.jpg","Agat Taşı","Zeyklc SAU20",429,336,{"id":392,"source_url":393,"license_code":358,"credit_html":394,"title":7,"description":8,"author":8,"original_width":360,"original_height":395},87527,"https:\u002F\u002Fgeocollections.info\u002Ffile\u002F93083","Photo: Unknown author — http:\u002F\u002Fcreativecommons.org\u002Flicenses\u002Fby-sa\u002F4.0\u002F, courtesy of \u003Ca href=\"https:\u002F\u002Fgeocollections.info\u002Ffile\u002F93083\" rel=\"noopener\">The Estonian Museum of Natural History\u003C\u002Fa> via Europeana",594,{"id":397,"source_url":398,"license_code":358,"credit_html":399,"title":7,"description":8,"author":8,"original_width":360,"original_height":400},87528,"https:\u002F\u002Fgeocollections.info\u002Ffile\u002F93113","Photo: Unknown author — http:\u002F\u002Fcreativecommons.org\u002Flicenses\u002Fby-sa\u002F4.0\u002F, courtesy of \u003Ca href=\"https:\u002F\u002Fgeocollections.info\u002Ffile\u002F93113\" rel=\"noopener\">The Estonian Museum of Natural History\u003C\u002Fa> via Europeana",831,{"id":402,"source_url":403,"license_code":404,"credit_html":405,"title":406,"description":407,"author":408,"original_width":409,"original_height":410},31551,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=146412295","CC0 1.0","Motekov, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=146412295\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","AGATE-COLLECTION GEORGI ZLATARSKI.jpg","AGATE FROM THE COLLECTION OF GEORGI ZLATARSKI","Motekov",1284,881,{"id":412,"source_url":413,"license_code":370,"credit_html":414,"title":415,"description":416,"author":408,"original_width":417,"original_height":418},31552,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=146853903","Motekov, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=146853903\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","AGATE-COLLECTION GEORGI ZLATARSKI 1.jpg","AGATE-COLLECTION GEORGI ZLATARSKI 1",1142,1104,{"id":420,"source_url":421,"license_code":404,"credit_html":422,"title":423,"description":424,"author":425,"original_width":426,"original_height":427},40629,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=152967585","LadyOfManyTalents, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=152967585\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Polished Rough Pink Agate Found Near Muddy Creek Bed, Estill County, KY.jpg","Pink Kentucky agate is a variety of agate that features soft pink tones and intricate banding. This particular specimen was found near a muddy creek bed in Estill County, Kentucky. After being cabbed and polished, its natural beauty is fully revealed. Agates are typically formed in volcanic rocks, and the pink coloring comes from trace minerals within the stone.","LadyOfManyTalents",2337,1753,{"id":429,"source_url":430,"license_code":370,"credit_html":431,"title":432,"description":433,"author":434,"original_width":435,"original_height":436},31558,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=181225883","Marie-Lan Taÿ Pamart, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=181225883\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate Rio Grande do Sul Caillois Donation MNHN n01.jpg","Agate from the Rio Grande do Sul, Brazil. Exhibition “Stones and Reveries: The Poetry and Minerals of Roger Caillois“ at the School of Jewelry Arts in Paris (November 6th, 2025—29th, 2026). Gallery of Mineralogy and Geology of the French National Museum of Natural History in Paris.","Marie-Lan Taÿ Pamart",6672,5391,{"id":438,"source_url":439,"license_code":370,"credit_html":440,"title":441,"description":433,"author":434,"original_width":442,"original_height":443},31559,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=181225884","Marie-Lan Taÿ Pamart, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=181225884\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate Rio Grande do Sul Caillois Donation MNHN n02.jpg",6619,5295,{"id":445,"source_url":446,"license_code":370,"credit_html":447,"title":448,"description":433,"author":434,"original_width":449,"original_height":449},31560,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=181225886","Marie-Lan Taÿ Pamart, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=181225886\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate Rio Grande do Sul Caillois Donation MNHN n03.jpg",4894,{"id":451,"source_url":452,"license_code":370,"credit_html":453,"title":454,"description":433,"author":434,"original_width":455,"original_height":456},31561,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=181225897","Marie-Lan Taÿ Pamart, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=181225897\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate Rio Grande do Sul Caillois Donation MNHN n06.jpg",5406,7208,{"id":458,"source_url":459,"license_code":370,"credit_html":460,"title":461,"description":462,"author":434,"original_width":463,"original_height":464},31562,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=181656612","Marie-Lan Taÿ Pamart, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=181656612\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Polyhedral agate Caillois Donation MNHN n01.jpg","Polyhedral agate from Sítio Garguelo, Brazil. Exhibition “Stones and Reveries: The Poetry and Minerals of Roger Caillois“ at the School of Jewelry Arts in Paris (November 6th, 2025—29th, 2026). Gallery of Mineralogy and Geology of the French National Museum of Natural History in Paris.",5426,7234,{"id":466,"source_url":467,"license_code":370,"credit_html":468,"title":469,"description":470,"author":434,"original_width":471,"original_height":472},31563,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=181658120","Marie-Lan Taÿ Pamart, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=181658120\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate Rio Grande do Sul Caillois Donation MNHN n18.jpg","Agate, likely from Rio Grande do Sul, Brazil. Exhibition “Stones and Reveries: The Poetry and Minerals of Roger Caillois“ at the School of Jewelry Arts in Paris (November 6th, 2025—29th, 2026). Gallery of Mineralogy and Geology of the French National Museum of Natural History in Paris.",5762,4609,{"id":474,"source_url":475,"license_code":370,"credit_html":476,"title":477,"description":470,"author":434,"original_width":478,"original_height":479},31564,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=181658126","Marie-Lan Taÿ Pamart, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=181658126\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate Rio Grande do Sul Caillois Donation MNHN n20.jpg",6477,4361,{"id":481,"source_url":482,"license_code":370,"credit_html":483,"title":484,"description":470,"author":434,"original_width":485,"original_height":486},31565,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=181683794","Marie-Lan Taÿ Pamart, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=181683794\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate Rio Grande do Sul Caillois Donation MNHN n23.jpg",6579,5264,{"id":488,"source_url":489,"license_code":370,"credit_html":490,"title":491,"description":492,"author":493,"original_width":494,"original_height":495},36301,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=170312517","W.carter, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=170312517\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Three light blue banded agate cabochons 2.jpg","Three light blue oval banded agate gemstone cabochons. Studio photography in Tuntorp, Brastad, Lysekil Municipality, Sweden.","W.carter",3723,2483,{"id":497,"source_url":498,"license_code":370,"credit_html":499,"title":500,"description":492,"author":493,"original_width":501,"original_height":502},36302,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=170312518","W.carter, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=170312518\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Three light blue banded agate cabochons 1.jpg",4717,2654,{"id":504,"source_url":505,"license_code":506,"credit_html":507,"title":508,"description":509,"author":510,"original_width":511,"original_height":512},36658,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=691107","CC BY-SA 3.0","No machine-readable author provided. Kluka assumed (based on copyright claims)., via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=691107\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agat polerowany, Botswana.jpg","agat polerowany, grudka; pochodzenie Botswana; autor zdjęcia Grzegorz Framski","No machine-readable author provided. Kluka assumed (based on copyright claims).",377,428,{"id":514,"source_url":515,"license_code":516,"credit_html":517,"title":518,"description":519,"author":520,"original_width":521,"original_height":522},36661,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=74174518","CC BY 2.0","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=74174518\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate 20 (30746156007).jpg","\"Agate\" is a rockhound\u002Fcollector term for irregularly- & concentrically-layered masses of microcrystalline quartz.  Individual layers consist of translucent or opaque, microcrystalline, fibrous quartz called chalcedony.  Impurities in different layers cause variations in color.  Many agate masses are simply geodes that have completely filled up with quartz.  Common agate colors are clearish-whitish-grayish, brownish-red, and yellowish-brown.  Commercial agates that occur in greens and blues and purples are almost always dyed (faked).","James St. John",2873,2306,{"id":524,"source_url":525,"license_code":516,"credit_html":526,"title":527,"description":519,"author":520,"original_width":528,"original_height":529},36662,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=74174519","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=74174519\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate 18 (30746155537).jpg",3311,2078,{"id":531,"source_url":532,"license_code":516,"credit_html":533,"title":534,"description":519,"author":520,"original_width":535,"original_height":536},36663,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=74174524","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=74174524\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate 13 (30746154057).jpg",3353,1973,{"id":538,"source_url":539,"license_code":516,"credit_html":540,"title":541,"description":519,"author":520,"original_width":542,"original_height":543},36664,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=74174527","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=74174527\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate 15 (30746154457).jpg",3553,2064,{"id":545,"source_url":546,"license_code":516,"credit_html":547,"title":548,"description":519,"author":520,"original_width":549,"original_height":550},36665,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=74174530","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=74174530\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate 10 (31814458148).jpg",1864,1843,{"id":552,"source_url":553,"license_code":554,"credit_html":555,"title":556,"description":8,"author":8,"original_width":557,"original_height":558},50985,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=127278","Public domain","Unknown author, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=127278\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate banded 750pix.jpg",750,626,{"id":560,"source_url":561,"license_code":506,"credit_html":562,"title":563,"description":564,"author":565,"original_width":566,"original_height":567},54990,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=10176082","Robert M. Lavinsky, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=10176082\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate-150541.jpg","\u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FAgate\" class=\"extiw\" title=\"en:Agate\">Agate\u003C\u002Fa> (Var.: \u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FAgate\" class=\"extiw\" title=\"en:Agate\">en:Agate\u003C\u002Fa>)\n\u003Cdl>\u003Cdd>\u003Cdl>\u003Cdd>Locality: \u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FAguascalientes\" class=\"extiw\" title=\"en:Aguascalientes\">Aguascalientes\u003C\u002Fa>, Mexico (\u003Ca rel=\"nofollow\" class=\"external text\" href=\"http:\u002F\u002Fwww.mindat.org\u002Floc-14258.html\">Locality at mindat.org\u003C\u002Fa>)\u003C\u002Fdd>\n\u003Cdd>Size: 4.9 x 3.3 x 1.4 cm.\u003C\u002Fdd>\n\u003Cdd>Goethite (basically, rust) can take on all sorts of forms. Here, it lines a cavity deep in the interior of a vug, underneath a layer of clear overgrowth that gives this fire agate its internal form! This is rare and precious material, sometimes used by very skilled jewelers. This is so pretty, though, it should remain a mineral specimen but you can see what a beautiful carving can be made to show off these bizarre inclusions. This is an intense and beautiful piece in person! It is so clear and strangely lightweight I mistook this for opal myself, as it was initially labeled here and is sometimes labeled by dealers. But it is technically a form of quartz var. agate, with goethite giving it the iridescence from underneath.\u003C\u002Fdd>\u003C\u002Fdl>\u003C\u002Fdd>\u003C\u002Fdl>","Robert M. Lavinsky",600,367,{"id":569,"source_url":570,"license_code":506,"credit_html":571,"title":572,"description":564,"author":565,"original_width":573,"original_height":574},54991,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=10176084","Robert M. Lavinsky, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=10176084\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate-150542.jpg",400,389,{"id":576,"source_url":577,"license_code":506,"credit_html":578,"title":579,"description":580,"author":565,"original_width":573,"original_height":581},54992,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=10176123","Robert M. Lavinsky, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=10176123\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate-156125.jpg","\u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FAgate\" class=\"extiw\" title=\"en:Agate\">Agate\u003C\u002Fa> (Var.: \u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FAgate\" class=\"extiw\" title=\"en:Agate\">en:Agate\u003C\u002Fa>)\n\u003Cdl>\u003Cdd>\u003Cdl>\u003Cdd>Locality: \u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FAguascalientes\" class=\"extiw\" title=\"en:Aguascalientes\">Aguascalientes\u003C\u002Fa>, Mexico (\u003Ca rel=\"nofollow\" class=\"external text\" href=\"http:\u002F\u002Fwww.mindat.org\u002Floc-14258.html\">Locality at mindat.org\u003C\u002Fa>)\u003C\u002Fdd>\n\u003Cdd>Size: 2.7 x 2.2 x 1.1 cm.\u003C\u002Fdd>\n\u003Cdd>These famous \"fire agates\", at their best, have all the flash of opals and are often confused with opal. They actually are formed by a thin layer of limonite covered in hard, transparent quartz, which is then polished to reveal the color. The good ones are quite rare; they are sometimes used in jewelry, though very hard to work with, so not many jewelers or lapidaries can work with the material, to get them exactly like this to where the colors come out, either for jewelry or just to keep as specimens. At any rate, here is a gorgeous specimen with a wonderful play of green and red.\u003C\u002Fdd>\u003C\u002Fdl>\u003C\u002Fdd>\u003C\u002Fdl>",358,{"id":583,"source_url":584,"license_code":506,"credit_html":585,"title":586,"description":587,"author":565,"original_width":566,"original_height":588},54993,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=10176357","Robert M. Lavinsky, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=10176357\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate-180670.jpg","\u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FAgate\" class=\"extiw\" title=\"en:Agate\">Agate\u003C\u002Fa> (Var.: \u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FAgate\" class=\"extiw\" title=\"en:Agate\">en:Agate\u003C\u002Fa>)\n\u003Cdl>\u003Cdd>\u003Cdl>\u003Cdd>Locality: \u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FAguascalientes\" class=\"extiw\" title=\"en:Aguascalientes\">Aguascalientes\u003C\u002Fa>, Mexico (\u003Ca rel=\"nofollow\" class=\"external text\" href=\"http:\u002F\u002Fwww.mindat.org\u002Floc-14258.html\">Locality at mindat.org\u003C\u002Fa>)\u003C\u002Fdd>\n\u003Cdd>Size: 3.9 x 2.9 x 1.7 cm.\u003C\u002Fdd>\n\u003Cdd>This is a polished specimen of \"fire agate\" that is very rare. It plays with light the way opal does, from fiery reds to neon green. This is a sizeable 20-gram specimen that is only about 10% matrix.\u003C\u002Fdd>\u003C\u002Fdl>\u003C\u002Fdd>\u003C\u002Fdl>",443,{"id":590,"source_url":591,"license_code":358,"credit_html":592,"title":593,"description":594,"author":595,"original_width":596,"original_height":597},55000,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=61156982","Lech Darski, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=61156982\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agat ognisty - Calvillo, Aguascalientes, Meksyk.jpg","Agat ognisty - Calvillo, Aguascalientes, Meksyk.","Lech Darski",4560,3040,{"id":599,"source_url":600,"license_code":358,"credit_html":601,"title":602,"description":594,"author":595,"original_width":603,"original_height":604},55005,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=88536319","Lech Darski, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=88536319\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Detail, Agat ognisty - Calvillo, Aguascalientes, Meksyk (cropped).jpg",1217,970,{"id":606,"source_url":607,"license_code":506,"credit_html":608,"title":609,"description":610,"author":595,"original_width":611,"original_height":249},63511,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=24623398","Lech Darski, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=24623398\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agat - Ojo de Laguna, Chihuahua, Meksyk.jpg","Agat - Ojo de Laguna, Chihuahua, Meksyk",3000,{"id":613,"source_url":614,"license_code":506,"credit_html":615,"title":616,"description":610,"author":595,"original_width":117,"original_height":617},63513,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=78311418","Lech Darski, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=78311418\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agat - Ojo de Laguna, Chihuahua, Meksyk (cropped).jpg",819,{"id":619,"source_url":620,"license_code":506,"credit_html":621,"title":622,"description":623,"author":595,"original_width":624,"original_height":204},63541,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=24623494","Lech Darski, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=24623494\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agat Lake Superior - Duluth, Minnesota, USA..jpg","Agate Lake Superior - Duluth, Minnesota, USA.",2988,{"id":626,"source_url":627,"license_code":358,"credit_html":628,"title":629,"description":630,"author":595,"original_width":631,"original_height":632},63542,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=35282037","Lech Darski, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=35282037\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agat Lake Superior - USA, Minnesota..jpg","Agat Lake Superior - USA, Minnesota.",4145,2763,{"id":634,"source_url":635,"license_code":636,"credit_html":637,"title":638,"description":639,"author":640,"original_width":641,"original_height":642},63543,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=52570252","CC BY 3.0","Brandon Menth, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=52570252\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate - panoramio - Brandon Menth.jpg","\u003Cp>Agate\n\u003C\u002Fp>\n\u003Cp>Photo that I took of one of my agates.\u003C\u002Fp>","Brandon Menth",3264,2448,{"id":644,"source_url":645,"license_code":358,"credit_html":646,"title":647,"description":648,"author":595,"original_width":649,"original_height":650},63544,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=69166645","Lech Darski, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=69166645\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agat Lake Superior (Agat z Jeziora Górnego)- Minnesota, USA.jpg","Agat Lake Superior (Agat z Jeziora Górnego)- Minnesota, USA.",3066,2044,{"id":652,"source_url":653,"license_code":358,"credit_html":654,"title":655,"description":648,"author":595,"original_width":656,"original_height":657},63546,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=78314133","Lech Darski, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=78314133\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agat Lake Superior (Agat z Jeziora Górnego)- Minnesota, USA (cropped).jpg",919,1051,{"id":659,"source_url":660,"license_code":358,"credit_html":661,"title":662,"description":630,"author":595,"original_width":663,"original_height":664},63558,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=88553123","Lech Darski, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=88553123\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate detail, Agat Lake Superior - USA, Minnesota. (cropped).jpg",2036,1632,{"id":666,"source_url":667,"license_code":516,"credit_html":668,"title":669,"description":670,"author":520,"original_width":671,"original_height":672},67624,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82926374","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82926374\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate nodule (Borden Formation, Lower Mississippian; eastern Kentucky, USA) 2 (32715144616).jpg","\u003Cp>Agate nodule from Kentucky, USA.\n\u003C\u002Fp>\u003Cp>This is the exterior of a solid agate nodule.  \"Agate\" is a rockhound\u002Fcollector term for irregularly- & concentrically-layered masses of microcrystalline quartz (not visible from the outside).  Individual layers consist of translucent or opaque, microcrystalline, fibrous quartz called chalcedony.  Impurities in different layers cause variations in color.  Many agate masses are simply geodes that have completely filled up with quartz.  Common agate colors are clearish-whitish-grayish, brownish-red, and yellowish-brown.  Commercial agates that occur in greens and blues and purples are almost always dyed (faked).\n\u003C\u002Fp>\u003Cp>Geologic context: nodule hosted in the Borden Formation, Lower Mississippian\n\u003C\u002Fp>\nLocality: unrecorded\u002Fundisclosed site in Powell County or Estill County or Jackson County or Madison County, eastern Kentucky, USA",2920,2664,{"id":674,"source_url":675,"license_code":516,"credit_html":676,"title":677,"description":678,"author":520,"original_width":679,"original_height":680},67625,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82926378","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82926378\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate (Borden Formation, Lower Mississippian; eastern Kentucky, USA) 3 (32756318585).jpg","\u003Cp>Agate nodule from Kentucky, USA.\n\u003C\u002Fp>\u003Cp>This is the interior of an agate nodule.  \"Agate\" is a rockhound\u002Fcollector term for irregularly- & concentrically-layered masses of microcrystalline quartz.  Individual layers consist of translucent or opaque, microcrystalline, fibrous quartz called chalcedony.  Impurities in different layers cause variations in color.  Many agate masses are simply geodes that have completely filled up with quartz.  Common agate colors are clearish-whitish-grayish, brownish-red, and yellowish-brown.  Commercial agates that occur in greens and blues and purples are almost always dyed (faked).\n\u003C\u002Fp>\u003Cp>Geologic context: nodule hosted in the Borden Formation, Lower Mississippian\n\u003C\u002Fp>\nLocality: unrecorded\u002Fundisclosed site in Powell County or Estill County or Jackson County or Madison County, eastern Kentucky, USA",3268,2480,{"id":682,"source_url":683,"license_code":516,"credit_html":684,"title":685,"description":678,"author":520,"original_width":686,"original_height":687},67626,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82926379","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82926379\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate (Borden Formation, Lower Mississippian; eastern Kentucky, USA) 5 (32756318275).jpg",2532,2388,{"id":689,"source_url":690,"license_code":516,"credit_html":691,"title":692,"description":678,"author":520,"original_width":693,"original_height":694},67627,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82926385","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82926385\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate (Borden Formation, Lower Mississippian; eastern Kentucky, USA) 10 (32756317865).jpg",3440,1692,{"id":696,"source_url":697,"license_code":516,"credit_html":698,"title":699,"description":678,"author":520,"original_width":700,"original_height":611},67628,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82926387","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82926387\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate (Borden Formation, Lower Mississippian; eastern Kentucky, USA) 11 (32632652021).jpg",4000,{"id":702,"source_url":703,"license_code":516,"credit_html":704,"title":705,"description":678,"author":520,"original_width":706,"original_height":707},67629,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82926392","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82926392\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate (Borden Formation, Lower Mississippian; eastern Kentucky, USA) 18 (32756316735).jpg",2504,2756,{"id":709,"source_url":710,"license_code":516,"credit_html":711,"title":712,"description":713,"author":520,"original_width":714,"original_height":715},67630,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82926472","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82926472\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate (Borden Formation, Lower Mississippian; eastern Kentucky, USA) 22 (33923149328).jpg","\u003Cp>Agate nodule from Kentucky, USA.\n\u003C\u002Fp>\u003Cp>This is the interior of an agate nodule.  \"Agate\" is a rockhound\u002Fcollector term for irregularly- & concentrically-layered masses of microcrystalline quartz.  Individual layers consist of translucent or opaque, microcrystalline, fibrous quartz called chalcedony.  Impurities in different layers cause variations in color.  Many agate masses are simply geodes that have completely filled up with quartz.  Common agate colors are clearish-whitish-grayish, brownish-red, and yellowish-brown.  Commercial agates that occur in greens and blues and purples are almost always dyed (faked).\n\u003C\u002Fp>\u003Cp>Geologic context: nodule hosted in the Borden Formation, Lower Mississippian\n\u003C\u002Fp>\nLocality: unrecorded\u002Fundisclosed site in Kentucky, USA",3429,2767,{"id":717,"source_url":718,"license_code":516,"credit_html":719,"title":720,"description":721,"author":520,"original_width":722,"original_height":723},67631,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974742","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974742\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate-filled geode (Brazil) 2 (32714553426).jpg","\u003Cp>Agate from Brazil. (public display, Carnegie Museum of Natural History, Pittsburgh, Pennsylvania, USA)\n\u003C\u002Fp>\u003Cp>\"Agate\" is a rockhound\u002Fcollector term for irregularly- & concentrically-layered masses of microcrystalline quartz.  Individual layers consist of translucent or opaque, microcrystalline, fibrous quartz called chalcedony.  Impurities in different layers cause variations in color.  Many agate masses are simply geodes that have completely filled up with quartz.  Common agate colors are clearish-whitish-grayish, brownish-red, and yellowish-brown.  Commercial agates that occur in greens and blues and purples are almost always dyed (faked).\n\u003C\u002Fp>\nThe whitish, glassy material at the center of this specimen is macrocrystalline quartz.",1552,1432,{"id":725,"source_url":726,"license_code":516,"credit_html":727,"title":728,"description":729,"author":520,"original_width":730,"original_height":731},67632,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974745","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974745\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate 7 (32755748235).jpg","\u003Cp>(public display, Carnegie Museum of Natural History, Pittsburgh, Pennsylvania, USA)\n\u003C\u002Fp>\n\"Agate\" is a rockhound\u002Fcollector term for irregularly- & concentrically-layered masses of microcrystalline quartz.  Individual layers consist of translucent or opaque, microcrystalline, fibrous quartz called chalcedony.  Impurities in different layers cause variations in color.  Many agate masses are simply geodes that have completely filled up with quartz.  Common agate colors are clearish-whitish-grayish, brownish-red, and yellowish-brown.  Commercial agates that occur in greens and blues and purples are almost always dyed (faked).",1641,1929,{"id":733,"source_url":734,"license_code":516,"credit_html":735,"title":736,"description":737,"author":520,"original_width":738,"original_height":739},67633,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974746","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974746\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate-filled geode (Condor Agate; Argentina) (31941551193).jpg","\u003Cp>Agate from Argentina. (public display, Carnegie Museum of Natural History, Pittsburgh, Pennsylvania, USA)\n\u003C\u002Fp>\n\"Agate\" is a rockhound\u002Fcollector term for irregularly- & concentrically-layered masses of microcrystalline quartz.  Individual layers consist of translucent or opaque, microcrystalline, fibrous quartz called chalcedony.  Impurities in different layers cause variations in color.  Many agate masses are simply geodes that have completely filled up with quartz.  Common agate colors are clearish-whitish-grayish, brownish-red, and yellowish-brown.  Commercial agates that occur in greens and blues and purples are almost always dyed (faked).",2124,1070,{"id":741,"source_url":742,"license_code":516,"credit_html":743,"title":744,"description":745,"author":520,"original_width":746,"original_height":235},67634,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974747","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974747\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate (Ankara, Turkey) (32755918225).jpg","\u003Cp>Agate from Turkey. (Jerry Schaber collection)\n\u003C\u002Fp>\n\"Agate\" is a rockhound\u002Fcollector term for irregularly- & concentrically-layered masses of microcrystalline quartz.  Individual layers consist of translucent or opaque, microcrystalline, fibrous quartz called chalcedony.  Impurities in different layers cause variations in color.  Many agate masses are simply geodes that have completely filled up with quartz.  Common agate colors are clearish-whitish-grayish, brownish-red, and yellowish-brown.  Commercial agates that occur in greens and blues and purples are almost always dyed (faked).",2770,{"id":748,"source_url":749,"license_code":516,"credit_html":750,"title":751,"description":752,"author":520,"original_width":753,"original_height":204},67636,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974763","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974763\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate (Wave Hill, Australia) 5 (32755915795).jpg","\u003Cp>Agate from Australia. (Jerry Schaber collection)\n\u003C\u002Fp>\n\"Agate\" is a rockhound\u002Fcollector term for irregularly- & concentrically-layered masses of microcrystalline quartz.  Individual layers consist of translucent or opaque, microcrystalline, fibrous quartz called chalcedony.  Impurities in different layers cause variations in color.  Many agate masses are simply geodes that have completely filled up with quartz.  Common agate colors are clearish-whitish-grayish, brownish-red, and yellowish-brown.  Commercial agates that occur in greens and blues and purples are almost always dyed (faked).",1642,{"id":755,"source_url":756,"license_code":516,"credit_html":757,"title":758,"description":752,"author":520,"original_width":759,"original_height":249},67637,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974766","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974766\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate (Wave Hill, Australia) 4 (31941597113).jpg",3008,{"id":761,"source_url":762,"license_code":516,"credit_html":763,"title":764,"description":765,"author":520,"original_width":766,"original_height":767},67641,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=153166639","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=153166639\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Dyed agate 3.jpg","\"Agate\" is a rockhound\u002Fcollector term for irregularly- & concentrically-layered masses of microcrystalline quartz.  Individual layers consist of translucent or opaque, microcrystalline, fibrous quartz called chalcedony.  Impurities in different layers cause variations in color.  Many agate masses are simply geodes that have completely filled up with quartz.  Common agate colors are clearish-whitish-grayish, brownish-red, and yellowish-brown.  Commercial agates, like this one, that occur in greens and blues and purples are almost always dyed (faked).",2197,1715,{"id":769,"source_url":770,"license_code":404,"credit_html":771,"title":772,"description":773,"author":774,"original_width":775,"original_height":776},68753,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=114846894","Edelmauswaldgeist, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=114846894\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Museum Mineralogia München 06.jpg","Quarz, Moos-Achat, Delessit ( Simbabwe)","Edelmauswaldgeist",5472,3648,{"id":778,"source_url":779,"license_code":506,"credit_html":780,"title":781,"description":782,"author":510,"original_width":783,"original_height":784},71443,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=655915","No machine-readable author provided. Kluka assumed (based on copyright claims)., via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=655915\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agat wstęgowy, grudka polerowana.jpg","agat wstegowy, grudka; autor zdjęcia Grzegorz Framski",547,571,{"id":786,"source_url":787,"license_code":358,"credit_html":788,"title":789,"description":790,"author":791,"original_width":792,"original_height":793},31549,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=129476998","Burkhard Mücke, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=129476998\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Achat Mineral aus Brasilien.jpg","Achat aufgeschnitten von Rio Grande do Sul im Museum Mineralogia München. Beim \u003Ca href=\"https:\u002F\u002Fde.wikipedia.org\u002Fwiki\u002FAchat\" class=\"extiw\" title=\"de:Achat\">Achat\u003C\u002Fa> handelt es sich um  eine mineralogische Varietät von \u003Ca href=\"https:\u002F\u002Fde.wikipedia.org\u002Fwiki\u002FQuarz\" class=\"extiw\" title=\"de:Quarz\">Quarz\u003C\u002Fa> in Gestalt von \u003Ca href=\"https:\u002F\u002Fde.wikipedia.org\u002Fwiki\u002FDruse_(Mineralogie)\" class=\"extiw\" title=\"de:Druse (Mineralogie)\">Drusen\u003C\u002Fa> und \u003Ca href=\"https:\u002F\u002Fde.wikipedia.org\u002Fwiki\u002FMandel_(Mineralogie)\" class=\"extiw\" title=\"de:Mandel (Mineralogie)\">Mandeln\u003C\u002Fa>","Burkhard Mücke",5100,3577,{"id":795,"source_url":796,"license_code":404,"credit_html":797,"title":798,"description":799,"author":425,"original_width":800,"original_height":801},31553,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=152967587","LadyOfManyTalents, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=152967587\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Lace Agate Found in Huzzah Creek, Missouri (with Mineral Oil for Better Visibility).png","Lace Agate is a variety of agate known for its swirling, lace-like patterns. This specimen  (viewed through an eye loupe) was found in Huzzah Creek, Missouri, and mineral oil has been applied to bring out the intricate details of the stone. The flowing bands of white, mustard, and brown are characteristic of lace agates, which are prized by collectors and lapidaries alike. Missouri’s rich geological landscape provides the perfect environment for these stones.",3024,4032,{"id":803,"source_url":804,"license_code":404,"credit_html":805,"title":806,"description":807,"author":425,"original_width":800,"original_height":801},31554,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=152967588","LadyOfManyTalents, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=152967588\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Another Lace Agate Found in Huzzah Creek, Missouri (with Mineral Oil for Better Visibility).png","This lace agate (viewed through an eye loupe) was also found in Huzzah Creek, Missouri. It features similarly detailed banding as the first, and mineral oil has been applied to enhance the visibility of the patterns. Lace agates from this region are known for their swirling lines and elegant designs, making them highly desirable for rock hounds and collectors. The mineral-rich environment of the area plays a key role in producing these beautiful stones.",{"id":809,"source_url":810,"license_code":516,"credit_html":811,"title":812,"description":813,"author":814,"original_width":815,"original_height":816},3473,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=84716511","Stephanie Clifford from Arlington, VA, USA, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=84716511\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate - Blue Lace - Chalcedony - Nambia (2932215721).jpg","Agate - Blue Lace - Chalcedony - Nambia","Stephanie Clifford from Arlington, VA, USA",355,362,{"id":818,"source_url":819,"license_code":516,"credit_html":820,"title":821,"description":822,"author":823,"original_width":824,"original_height":825},3861,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=105250816","MAURO CATEB from Brazil, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=105250816\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Blue agate pebble (6523571107).jpg","Agate or banded quartz. Gemstone illuminated from behind on a light table, to enhance the bands.","MAURO CATEB from Brazil",1679,1289,{"id":827,"source_url":828,"license_code":358,"credit_html":829,"title":830,"description":831,"author":832,"original_width":833,"original_height":834},7854,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=12462069","Didier Descouens, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=12462069\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Enhydros.jpg","Agate enhydros. \n\u003Cdl>\u003Cdd>\u003Cdl>\u003Cdd>The water of crystallization is trapped inside the geode, sometimes with a gaseous phase. Only the surface part of the agate nodule has been sawn and polished to reveal the two phases through transparency.\u003C\u002Fdd>\n\u003Cdd>Locality : Brasil.\u003C\u002Fdd>\n\u003Cdd>Size 13.5x11.6 cm\u003C\u002Fdd>\u003C\u002Fdl>\u003C\u002Fdd>\u003C\u002Fdl>","Didier Descouens",6048,5000,{"id":836,"source_url":837,"license_code":506,"credit_html":838,"title":839,"description":840,"author":841,"original_width":842,"original_height":843},21419,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=32668349","峠 武宏, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=32668349\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Oregon002.jpg","Beach Agate with Sagenite from Central Oregon Coast, near Newport and Yachats, Oregon, U.S.A.","峠 武宏",4704,3136,{"id":845,"source_url":846,"license_code":506,"credit_html":847,"title":848,"description":840,"author":841,"original_width":849,"original_height":850},21420,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=88547723","峠 武宏, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=88547723\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Beach Agate with Sagenite from Central Oregon Coast, near Newport and Yachats, Oregon detail, from- Oregon002 (cropped).jpg",1416,1134,{"id":852,"source_url":853,"license_code":506,"credit_html":854,"title":855,"description":856,"author":857,"original_width":858,"original_height":859},21767,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=5945460","Ra'ike (see also: de:Benutzer:Ra'ike), via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=5945460\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Quartz - snake-skin agate from Mexico.jpg","\u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FQuartz\" class=\"extiw\" title=\"en:Quartz\">Quartz\u003C\u002Fa> - variety snake-skin agate from Mexico","Ra'ike (see also: de:Benutzer:Ra'ike)",2700,1900,{"id":861,"source_url":862,"license_code":506,"credit_html":863,"title":864,"description":856,"author":857,"original_width":865,"original_height":866},21768,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=78311486","Ra'ike (see also: de:Benutzer:Ra'ike), via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=78311486\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Quartz - snake-skin agate from Mexico (cropped).jpg",648,1021,{"id":868,"source_url":869,"license_code":506,"credit_html":870,"title":871,"description":856,"author":857,"original_width":872,"original_height":873},21769,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=78311497","Ra'ike (see also: de:Benutzer:Ra'ike), via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=78311497\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Detail, Quartz - snake-skin agate from Mexico (cropped).jpg",773,332,{"id":875,"source_url":876,"license_code":516,"credit_html":877,"title":878,"description":879,"author":520,"original_width":880,"original_height":881},24164,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974794","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974794\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Thunder Egg Agate (Priday Blue Bed, John Day Formation, Miocene; near Madras, Oregon, USA) 1 (32744937906).jpg","\u003Cp>Agate (\"Thunder Egg\") from the Tertiary of Oregon, USA.\n\u003C\u002Fp>\u003Cp>\"Agate\" is a rockhound\u002Fcollector term for cavities in rocks (usually sedimentary rocks such as limestone or igneous rocks such as basalt) that have been partially or completely filled with irregularly concentric layers of microcrystalline, fibrous quartz (chalcedony - SiO2).  Agate is quartz.\n\u003C\u002Fp>\u003Cp>\"Thunder eggs\" are agate-filled masses that fill former cavities in volcanic rocks (see Colburn, 2004 for more info.).\n\u003C\u002Fp>\u003Cp>Stratigraphy: Priday Blue Bed, John Day Formation, Miocene\n\u003C\u002Fp>\u003Cp>Locality: Richardson Ranch (Richardson's Rock Ranch), northeast of the town of Madras, Jefferson County, north-central Oregon, USA\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Reference cited:\n\u003C\u002Fp>\nColburn (2004) - The Formation of Thundereggs (Lithophysae).  493 pp. (<a href=\"\u003Ca rel=\"nofollow\" class=\"external free\" href=\"http:\u002F\u002Fwww.cvmineralclub.org\u002FMAIN\u002FPages\u002FMembers\">http:\u002F\u002Fwww.cvmineralclub.org\u002FMAIN\u002FPages\u002FMembers\u003C\u002Fa> Articles\u002FJack Marcy\u002FThe Formation of Thundereggs-Revised 2004.pdf\" rel=\"nofollow\">www.cvmineralclub.org\u002FMAIN\u002FPages\u002FMembers%20Articles\u002FJack%...<\u002Fa>) (This long document may take a little while to load on your computer.)",3020,2992,{"id":883,"source_url":884,"license_code":516,"credit_html":885,"title":886,"description":879,"author":520,"original_width":887,"original_height":888},24165,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974867","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974867\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Thunder Egg Agate (Priday Blue Bed, John Day Formation, Miocene; near Madras, Oregon, USA) 2 (34416129410).jpg",2389,2412,{"id":890,"source_url":891,"license_code":516,"credit_html":892,"title":893,"description":894,"author":520,"original_width":502,"original_height":895},24167,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=84622668","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=84622668\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Thunder egg quartz (Baker Ranch Agate Mine, Luna County, New Mexico, USA) (34346707651).jpg","\u003Cp>Quartz (\"Thunder Egg\") from New Mexico, USA.\n\u003C\u002Fp>\u003Cp>A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties.  At its simplest, a mineral is a naturally-occurring solid chemical.  Currently, there are over 5100 named and described minerals - about 200 of them are common and about 20 of them are very common.  Mineral classification is based on anion chemistry.  Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.\n\u003C\u002Fp>\u003Cp>The silicates are the most abundant and chemically complex group of minerals.  All silicates have silica as the basis for their chemistry.  \"Silica\" refers to SiO2 chemistry.  The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4.  Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens \"belong\" to each silicon.  The resulting formula for silica is thus SiO2, not SiO4.\n\u003C\u002Fp>\u003Cp>The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2).  All other silicates have silica + impurities.  Many silicates have a significant percentage of aluminum (the aluminosilicates).\n\u003C\u002Fp>\u003Cp>Quartz (silicon dioxide\u002Fsilica - SiO2) is the most common mineral in the Earth's crust.  It is composed of the two most abundant elements in the crust - oxygen and silicon.  It has a glassy, nonmetallic luster, is commonly clearish to whitish to grayish in color, has a white streak, is quite hard (H≡7), forms hexagonal crystals, has no cleavage, and has conchoidal fracture.  Quartz can be any color: clear, white, gray, black, brown, pink, red, purple, blue, green, orange, etc.\n\u003C\u002Fp>\u003Cp>The quartz specimen shown above is a \"thunder egg\", which refers to agate- and\u002For quartz-filled masses that fill former cavities in rocks.\n\u003C\u002Fp>\u003Cp>Locality: Baker Mine (Baker Ranch Agate Mine), Luna County, southwestern New Mexico, USA\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of quartz and amethyst\n\u003C\u002Fp>\n<a href=\"\u003Ca rel=\"nofollow\" class=\"external free\" href=\"http:\u002F\u002Fwww.mindat.org\u002Fgallery.php?min=3337\">http:\u002F\u002Fwww.mindat.org\u002Fgallery.php?min=3337\u003C\u002Fa>\" rel=\"nofollow\">www.mindat.org\u002Fgallery.php?min=3337<\u002Fa>",2462,{"id":897,"source_url":898,"license_code":516,"credit_html":899,"title":900,"description":901,"author":520,"original_width":902,"original_height":903},24168,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=110930860","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=110930860\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Thunder Egg Agate (Priday Blue Bed, John Day Formation, Miocene; near Madras, Oregon, USA) 5.jpg","Agate (\"Thunder Egg\") from the Tertiary of Oregon, USA. (9.2 centimeters across at its widest)\n\u003Cp>\"Agate\" is a rockhound\u002Fcollector term for cavities in rocks (usually sedimentary rocks such as limestone or igneous rocks such as basalt) that have been partially or completely filled with irregularly concentric layers of microcrystalline, fibrous quartz (chalcedony - SiO2).  Agate is quartz.\n\u003C\u002Fp>\u003Cp>\"Thunder eggs\" are agate-filled masses that fill former cavities in volcanic rocks (see Colburn, 2004 for more info.).\n\u003C\u002Fp>\u003Cp>Stratigraphy: unrecorded (but probably the Priday Blue Bed, John Day Formation, Miocene)\n\u003C\u002Fp>\u003Cp>Locality: unrecorded site in Oregon, USA (but probably Richardson Ranch \u002F Richardson's Rock Ranch, northeast of the town of Madras, Jefferson County, north-central Oregon)\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Reference cited:\n\u003C\u002Fp>\nColburn (2004) - The Formation of Thundereggs (Lithophysae).  493 pp.",4406,3591,{"id":905,"source_url":906,"license_code":516,"credit_html":907,"title":908,"description":909,"author":520,"original_width":910,"original_height":911},24169,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=111293921","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=111293921\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Thunder Egg Agate (Priday Blue Bed, John Day Formation, Miocene; near Madras, Oregon, USA) 6.jpg","Agate (\"Thunder Egg\") from the Tertiary of Oregon, USA. (cut & polished surface; 9.9 centimeters across at its widest)\n\u003Cp>\"Agate\" is a rockhound\u002Fcollector term for cavities in rocks (usually sedimentary rocks such as limestone or igneous rocks such as basalt) that have been partially or completely filled with irregularly concentric layers of microcrystalline, fibrous quartz (chalcedony - SiO2).  Agate is quartz.\n\u003C\u002Fp>\u003Cp>\"Thunder eggs\" are agate-filled masses that fill former cavities in volcanic rocks (see Colburn, 2004 for more info.).  The agate in this specimen has formed subtle, thin, horizontal laminations.  The original \"down\" direction due to gravity is evident - such features are called geopetal structures.\n\u003C\u002Fp>\u003Cp>Stratigraphy: unrecorded (but probably the Priday Blue Bed, John Day Formation, Miocene)\n\u003C\u002Fp>\u003Cp>Locality: unrecorded site in Oregon, USA (but probably Richardson Ranch \u002F Richardson's Rock Ranch, northeast of the town of Madras, Jefferson County, north-central Oregon)\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Reference cited:\n\u003C\u002Fp>\nColburn (2004) - The Formation of Thundereggs (Lithophysae).  493 pp.",4622,3746,{"id":913,"source_url":914,"license_code":370,"credit_html":915,"title":916,"description":917,"author":918,"original_width":919,"original_height":919},32580,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=186473071","I2Overcome, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=186473071\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Grape agate cluster.png","Grape agate (botryoidal amethyst) cluster from Indonesia","I2Overcome",1772,{"id":921,"source_url":922,"license_code":506,"credit_html":923,"title":924,"description":925,"author":926,"original_width":927,"original_height":928},36221,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=17476448","Mauro Cateb, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=17476448\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Artificially colored agate.jpg","Artificially colored blue agate cabochon. Photo : Mauro Cateb","Mauro Cateb",4320,3240,{"id":930,"source_url":931,"license_code":358,"credit_html":932,"title":933,"description":934,"author":935,"original_width":936,"original_height":937},36222,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=30625823","Anıl Öztaş, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=30625823\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Blauer Achat -- 2014 -- 2352.jpg","A blue \u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002Fen:Agate\" class=\"extiw\" title=\"w:en:Agate\">agate\u003C\u002Fa> slice.","Anıl Öztaş",2060,1536,{"id":939,"source_url":940,"license_code":516,"credit_html":941,"title":942,"description":943,"author":520,"original_width":944,"original_height":945},36225,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=55412911","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=55412911\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Holley Blue Agate, Sweet Home, OR (3.9 cm).jpg","\u003Cp>Agate from Oregon, USA. (top specimen is 3.9 cm across)\n\u003C\u002Fp>\u003Cp>\"Agate\" is a rockhound\u002Fcollector term for cavities in rocks (usually sedimentary rocks such as limestone or igneous rocks such as basalt) that have been partially or completely filled with irregularly concentric layers of microcrystalline, fibrous quartz (chalcedony - SiO2).  Agate is quartz.\n\u003C\u002Fp>\u003Cp>These two samples are \"Holley Blue Agate\" from Oregon.  They are composed of pale purplish chalcedony.  This material is famous, but is never accompanied by useful information, in terms of specific locality or geologic context.  I don't know what the host rock is, or the stratigraphy, or the age.  I suspect that this chalcedony fills vesicles in Cenozoic-aged lava.  The locality does not appear to be specified anywhere in the literature.  The best locality information I have is “Holley Mountain” (wherever that is) near the towns of Holley or Sweet Home or Lebanon.\n\u003C\u002Fp>\nLocality: Linn County, western Oregon, USA",1349,769,{"id":947,"source_url":948,"license_code":516,"credit_html":949,"title":950,"description":951,"author":520,"original_width":952,"original_height":953},36227,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974885","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974885\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Holley Blue Agate (near Sweet Home, Oregon, USA) 4 (46945278161).jpg","\u003Cp>Agate from Oregon, USA.\n\u003C\u002Fp>\u003Cp>\"Agate\" is a rockhound\u002Fcollector term for cavities in rocks (usually sedimentary rocks such as limestone or igneous rocks such as basalt) that have been partially or completely filled with irregularly concentric layers of microcrystalline, fibrous quartz (chalcedony - SiO2).  Agate is quartz.\n\u003C\u002Fp>\u003Cp>This sample is \"Holley Blue Agate\" (a.k.a. \"Calapooia Purple Agate\") from Oregon, and is composed of pale purplish chalcedony.  This material is hosted in weathered\u002Fdecomposed tholeiitic basalts of the Little Butte Volcanic Series (Oligocene).\n\u003C\u002Fp>\nLocality: attributed to Scott Mountain, ~6.4 miles west of the town of Sweet Home, Linn County, western Oregon, USA",1833,1318,{"id":955,"source_url":956,"license_code":516,"credit_html":957,"title":958,"description":951,"author":520,"original_width":959,"original_height":960},36228,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974886","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974886\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Holley Blue Agate (near Sweet Home, Oregon, USA) 2 (33069676258).jpg",1874,1216,{"id":962,"source_url":963,"license_code":516,"credit_html":964,"title":965,"description":951,"author":520,"original_width":966,"original_height":418},36229,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974888","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974888\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Holley Blue Agate (near Sweet Home, Oregon, USA) 5 (46945277491).jpg",1535,{"id":968,"source_url":969,"license_code":516,"credit_html":970,"title":971,"description":972,"author":520,"original_width":973,"original_height":866},36232,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=97912717","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=97912717\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Holley Blue Agate (Linn County, Oregon, USA) 12.jpg","Agate from Oregon, USA.\n\u003Cp>\"Agate\" is a rockhound\u002Fcollector term for cavities in rocks (usually sedimentary rocks such as limestone or igneous rocks such as basalt) that have been partially or completely filled with irregularly concentric layers of microcrystalline, fibrous quartz (chalcedony - SiO2).  Agate is quartz.\n\u003C\u002Fp>\u003Cp>Seen here is \"Holley Blue Agate\" (a.k.a. \"Calapooia Purple Agate\") from Oregon - it's composed of lavender- to purplish-colored chalcedony.  This material is hosted in weathered\u002Fdecomposed tholeiitic basalts of the Little Butte Volcanic Series (Oligocene).\n\u003C\u002Fp>\nLocality: unrecorded\u002Fundisclosed site in Linn County, western Oregon, USA",1854,{"id":975,"source_url":976,"license_code":516,"credit_html":977,"title":978,"description":972,"author":520,"original_width":979,"original_height":980},36233,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=97912719","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=97912719\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Holley Blue Agate (Linn County, Oregon, USA) 11.jpg",790,1684,{"id":982,"source_url":983,"license_code":516,"credit_html":984,"title":985,"description":972,"author":520,"original_width":986,"original_height":54},36234,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=97912721","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=97912721\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Holley Blue Agate (Linn County, Oregon, USA) 10.jpg",1802,{"id":988,"source_url":989,"license_code":516,"credit_html":990,"title":991,"description":972,"author":520,"original_width":181,"original_height":992},36235,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=97912722","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=97912722\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Holley Blue Agate (Linn County, Oregon, USA) 9.jpg",1274,{"id":994,"source_url":995,"license_code":516,"credit_html":996,"title":997,"description":972,"author":520,"original_width":998,"original_height":999},36236,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=97912724","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=97912724\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Holley Blue Agate (Linn County, Oregon, USA) 8.jpg",1797,1030,{"id":1001,"source_url":1002,"license_code":516,"credit_html":1003,"title":1004,"description":972,"author":520,"original_width":1005,"original_height":1006},36237,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=97912725","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=97912725\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Holley Blue Agate (Linn County, Oregon, USA) 7.jpg",3138,1934,{"id":1008,"source_url":1009,"license_code":358,"credit_html":1010,"title":1011,"description":1012,"author":1013,"original_width":1014,"original_height":1015},36970,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=47687442","Myself., via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=47687442\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate, amethyste, quartz.jpg","A slice of \u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FSillicate\" class=\"extiw\" title=\"w:Sillicate\">silicates\u003C\u002Fa> of my collection: \u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002Fagate\" class=\"extiw\" title=\"w:agate\">agate\u003C\u002Fa>, \u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002Famethyst\" class=\"extiw\" title=\"w:amethyst\">amethyst\u003C\u002Fa>, \u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002Fquartz\" class=\"extiw\" title=\"w:quartz\">quartz\u003C\u002Fa> from Baia-Sprie, \u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FMaramure%C8%99\" class=\"extiw\" title=\"w:Maramureș\">Maramureș\u003C\u002Fa>","Myself.",3207,3806,{"id":1017,"source_url":1018,"license_code":358,"credit_html":1019,"title":1020,"description":1021,"author":1022,"original_width":800,"original_height":801},38378,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=165063289","Bobjgalindo, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=165063289\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Carnelian Agate, Oregon.jpg","Carnelian Agate, Oregon","Bobjgalindo",{"id":1024,"source_url":1025,"license_code":506,"credit_html":1026,"title":1027,"description":1028,"author":841,"original_width":842,"original_height":843},52066,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=32651875","峠 武宏, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=32651875\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Dendritic agate with three dendrite occurances.jpg","Dendritic Agate from Ken River, Bundelkhand Region, India",{"id":1030,"source_url":1031,"license_code":506,"credit_html":1032,"title":1033,"description":1028,"author":841,"original_width":1034,"original_height":1035},52069,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=78312618","峠 武宏, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=78312618\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Dendritic agate (cropped).jpg",980,1242,{"id":1037,"source_url":1038,"license_code":358,"credit_html":1039,"title":1040,"description":1041,"author":926,"original_width":1042,"original_height":1043},52072,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=118588961","Mauro Cateb, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=118588961\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Brazilian dendritic agate.jpg","Dendritic agate from Brazil. 11.5 x 8.5 cm",3202,2598,{"id":1045,"source_url":1046,"license_code":516,"credit_html":1047,"title":1048,"description":1049,"author":520,"original_width":1050,"original_height":1051},52080,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126617165","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126617165\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Dendritic agate 4.jpg","\"Dendritic agate\" is a rockhound term applied to fine-grained quartz \u002F chalcedony having dark-colored, irregularly-shaped to branching inclusions of one or more opaque minerals.\nLocality: unrecorded \u002F undisclosed",2492,1464,{"id":1053,"source_url":1054,"license_code":516,"credit_html":1055,"title":1056,"description":1049,"author":520,"original_width":1050,"original_height":1051},52081,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126617168","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126617168\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Dendritic agate 3.jpg",{"id":1058,"source_url":1059,"license_code":516,"credit_html":1060,"title":1061,"description":1049,"author":520,"original_width":1050,"original_height":1051},52082,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126617169","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126617169\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Dendritic agate 2.jpg",{"id":1063,"source_url":1064,"license_code":516,"credit_html":1065,"title":1066,"description":1049,"author":520,"original_width":1050,"original_height":1067},52083,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126617171","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126617171\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Dendritic agate 1.jpg",1494,{"id":1069,"source_url":1070,"license_code":554,"credit_html":1071,"title":1072,"description":1073,"author":1074,"original_width":1075,"original_height":1076},54985,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=1995626","Wraithwing at English Wikipedia, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=1995626\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Fireagate.JPG","I took this photo myself of my own fire agate","Wraithwing at English Wikipedia",640,480,{"id":1078,"source_url":1079,"license_code":506,"credit_html":1080,"title":1081,"description":1082,"author":1083,"original_width":686,"original_height":1084},54986,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=2214889","Brocken Inaglory, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=2214889\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Fire agate.jpg","\u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002Fen:Fire_Agate\" class=\"extiw\" title=\"w:en:Fire Agate\">Fire agate\u003C\u002Fa>","Brocken Inaglory",1509,{"id":1086,"source_url":1087,"license_code":554,"credit_html":1088,"title":1089,"description":1090,"author":1091,"original_width":776,"original_height":1092},54988,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=4932457","Lysergian, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=4932457\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Sagenitic Fire Agate 01.jpg","Sagenitic Fire Agate","Lysergian",2736,{"id":1094,"source_url":1095,"license_code":506,"credit_html":1096,"title":1097,"description":1098,"author":565,"original_width":566,"original_height":1099},54989,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=10176079","Robert M. Lavinsky, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=10176079\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate-149421.jpg","\u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FAgate\" class=\"extiw\" title=\"en:Agate\">Agate\u003C\u002Fa> (Var.: \u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FAgate\" class=\"extiw\" title=\"en:Agate\">en:Agate\u003C\u002Fa>)\n\u003Cdl>\u003Cdd>\u003Cdl>\u003Cdd>Locality: \u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FAguascalientes\" class=\"extiw\" title=\"en:Aguascalientes\">Aguascalientes\u003C\u002Fa>, Mexico (\u003Ca rel=\"nofollow\" class=\"external text\" href=\"http:\u002F\u002Fwww.mindat.org\u002Floc-14258.html\">Locality at mindat.org\u003C\u002Fa>)\u003C\u002Fdd>\n\u003Cdd>Size: 6.5 x 5.9 x 2.5 cm.\u003C\u002Fdd>\n\u003Cdd>NOTE: the apparent surface flaws on this specimen are not there in person - they are just photo artifacts; in person, the surface is polished and glassy and there are no dull spots or lines as the pic implies). Elsewhere in this set of auctions, we have a goethite and mentioned that this mineral (basically, rust) can take on all sorts of forms. Here, it is goethite lining the cavity deep in the interior of the vug, underneath a layer of agate that gives this fire agate its internal form under the gem silica itself! This is rare and precious material. This is so pretty, though, it should remain a mineral specimen. This is an intense and beautiful piece in person!\u003C\u002Fdd>\u003C\u002Fdl>\u003C\u002Fdd>\u003C\u002Fdl>",492,{"id":1101,"source_url":1102,"license_code":506,"credit_html":1103,"title":1104,"description":1105,"author":1106,"original_width":641,"original_height":172},54994,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=20199422","Malinadams, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=20199422\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Fire Agate.jpg","This is an example of a Fire Agate before it has been cut and processed. It was found in New Mexico by geologist Dr. Jerry E. Adams, New Mexico State University.","Malinadams",{"id":1108,"source_url":1109,"license_code":506,"credit_html":1110,"title":1111,"description":1112,"author":1113,"original_width":1114,"original_height":1115},54995,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=25694882","Maricopa Mining LLC, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=25694882\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","High Grade Slaughter Mountain Arizona Fire Agate Rough.jpg","High Grade Slaughter Mountain Arizona Fire Agate Rough","Maricopa Mining LLC",1288,1200,{"id":1117,"source_url":1118,"license_code":516,"credit_html":1119,"title":1120,"description":1121,"author":1122,"original_width":1123,"original_height":937},55007,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=92637474","Jessa and Mark Anderson from Barron, Wisconsin, USA, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=92637474\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Fire Agate Gem - Flickr - Different Seasons Jewelry.jpg","Amazing crack-like pattern that changes color between red and purple with a background that flashes between green, orange and blue.","Jessa and Mark Anderson from Barron, Wisconsin, USA",2048,{"id":1125,"source_url":1126,"license_code":506,"credit_html":1127,"title":1128,"description":1129,"author":1130,"original_width":1131,"original_height":1132},55221,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=32671310","Sailko, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=32671310\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Museo di mineralogia, trasperenze, agata (top), liddicoatite dal madagascar (sx) e fluorite da cina (dx).JPG","Museo di storia naturale (Florence) - Mineralogy section","Sailko",2976,2328,{"id":1134,"source_url":1135,"license_code":358,"credit_html":1136,"title":1137,"description":1138,"author":1139,"original_width":1140,"original_height":1141},57319,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=86319528","JJ Harrison (https:\u002F\u002Fwww.jjharrison.com.au\u002F), via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=86319528\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Botryoidal Purple Grape Agate Chalcedony from Indonesia.jpg","\u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FBotryoidal\" class=\"extiw\" title=\"w:Botryoidal\">Botryoidal\u003C\u002Fa> Purple \u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FGrape_Agate\" class=\"extiw\" title=\"w:Grape Agate\">Grape Agate\u003C\u002Fa> \u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FChalcedony\" class=\"extiw\" title=\"w:Chalcedony\">Chalcedony\u003C\u002Fa> from Indonesia.","JJ Harrison (https:\u002F\u002Fwww.jjharrison.com.au\u002F)",4713,3142,{"id":1143,"source_url":1144,"license_code":370,"credit_html":1145,"title":1146,"description":1147,"author":1148,"original_width":1149,"original_height":1150},57323,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=186106328","John Sobolewski, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=186106328\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Grape agate 1163004.jpg","Grape agate (botryoidal amethyst) from Mamuju Regency, West Sulawesi Province, Indonesia","John Sobolewski",1024,768,{"id":1152,"source_url":1153,"license_code":404,"credit_html":1154,"title":1155,"description":1156,"author":1157,"original_width":1158,"original_height":1159},57324,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=186108210","Muhammad Majid, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=186108210\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Grape agate 1170969.jpg","Blue-green and purple grape agate from Mamuju Regency, West Sulawesi Province, Indonesia","Muhammad Majid",767,876,{"id":1161,"source_url":1162,"license_code":358,"credit_html":1163,"title":1164,"description":1138,"author":1139,"original_width":1140,"original_height":1165},57326,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=189061955","JJ Harrison (https:\u002F\u002Fwww.jjharrison.com.au\u002F), via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=189061955\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Botryoidal Purple Grape Agate Chalcedony from Indonesia (cropped).jpg",2653,{"id":1167,"source_url":1168,"license_code":516,"credit_html":1169,"title":1170,"description":1171,"author":520,"original_width":1172,"original_height":1173},67635,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974756","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974756\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate (Nowy Kosicol, Poland) (31912720284).jpg","\u003Cp>Agate from Poland. (Jerry Schaber collection)\n\u003C\u002Fp>\n\"Agate\" is a rockhound\u002Fcollector term for irregularly- & concentrically-layered masses of microcrystalline quartz.  Individual layers consist of translucent or opaque, microcrystalline, fibrous quartz called chalcedony.  Impurities in different layers cause variations in color.  Many agate masses are simply geodes that have completely filled up with quartz.  Common agate colors are clearish-whitish-grayish, brownish-red, and yellowish-brown.  Commercial agates that occur in greens and blues and purples are almost always dyed (faked).",2386,1959,{"id":1175,"source_url":1176,"license_code":554,"credit_html":1177,"title":1178,"description":1179,"author":1180,"original_width":1181,"original_height":1182},68735,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=1981082","Bhbritt54 at English Wikipedia, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=1981082\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Montana Moss Agate.jpg","Brooks Britt Specimen and Photo","Bhbritt54 at English Wikipedia",2304,1728,{"id":1184,"source_url":1185,"license_code":506,"credit_html":1186,"title":1187,"description":1188,"author":1189,"original_width":1190,"original_height":1191},68736,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=25747053","Original images Montanabw and Bhbritt54, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=25747053\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Montana official gemstones horizontal.jpg","The sapphire and the agate are Montana's official gemstones","Original images Montanabw and Bhbritt54",686,333,{"id":1193,"source_url":1194,"license_code":370,"credit_html":1195,"title":1196,"description":1197,"author":1198,"original_width":1199,"original_height":1200},68739,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=65247960","Unknown authorUnknown author, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=65247960\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Brooch (AM 1979.6-1).jpg","Brooch, rectangular moss agate brooch in gold mount","Unknown authorUnknown author",2592,1944,{"id":1202,"source_url":1203,"license_code":370,"credit_html":1204,"title":1205,"description":1197,"author":1198,"original_width":1199,"original_height":1200},68740,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=65247969","Unknown authorUnknown author, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=65247969\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Brooch (AM 1979.6-6).jpg",{"id":1207,"source_url":1208,"license_code":358,"credit_html":1209,"title":1210,"description":1211,"author":1212,"original_width":1213,"original_height":1214},68746,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=78313142","Hannes Grobe, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=78313142\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Moss agate detail (cropped).jpg","Moss agate as pendant","Hannes Grobe",2880,3672,{"id":1216,"source_url":1217,"license_code":358,"credit_html":1218,"title":1219,"description":1220,"author":1221,"original_width":1222,"original_height":1115},68747,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=81061625","Tiit Hunt, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=81061625\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Estonian Museum of Natural History Specimen No 178073 photo (g229 g229-436 jpg).jpg","Moss agate cabochon from Australia. More info \u003Ca rel=\"nofollow\" class=\"external text\" href=\"http:\u002F\u002Fgeocollections.info\u002Ffile\u002F61198\">about this file\u003C\u002Fa> and \u003Ca rel=\"nofollow\" class=\"external text\" href=\"http:\u002F\u002Fgeocollections.info\u002Fspecimen\u002F178073\">about this specimen\u003C\u002Fa> at \u003Ca rel=\"nofollow\" class=\"external text\" href=\"http:\u002F\u002Fgeocollections.info\u002F\">geocollections.info\u003C\u002Fa>","Tiit Hunt",1600,{"id":1224,"source_url":1225,"license_code":358,"credit_html":1226,"title":1227,"description":1228,"author":1221,"original_width":1222,"original_height":1115},68748,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=81517936","Tiit Hunt, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=81517936\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Estonian Museum of Natural History Specimen No 178064 photo (g229 g229-427 jpg).jpg","Moss agate cabochon from Australia. More info \u003Ca rel=\"nofollow\" class=\"external text\" href=\"http:\u002F\u002Fgeocollections.info\u002Ffile\u002F61205\">about this file\u003C\u002Fa> and \u003Ca rel=\"nofollow\" class=\"external text\" href=\"http:\u002F\u002Fgeocollections.info\u002Fspecimen\u002F178064\">about this specimen\u003C\u002Fa> at \u003Ca rel=\"nofollow\" class=\"external text\" href=\"http:\u002F\u002Fgeocollections.info\u002F\">geocollections.info\u003C\u002Fa>",{"id":1230,"source_url":1231,"license_code":358,"credit_html":1232,"title":1233,"description":1234,"author":493,"original_width":1235,"original_height":1236},68754,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=157499581","W.carter, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=157499581\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Four moss agate cabochons.jpg","Four moss agate cabochons. Studio photography in Vibble, Visby, Gotland, Sweden.",1295,971,{"id":1238,"source_url":1239,"license_code":506,"credit_html":1240,"title":1241,"description":1242,"author":1243,"original_width":1244,"original_height":1245},82822,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=15985531","Przykuta, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=15985531\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Muzeum Złota w Złotoryi agat z Nowego Kościoła 21.07.2011 p.jpg","Agat ze wsi Nowy Kościół w Muzeum Złota w Złotoryi","Przykuta",1644,1428,{"id":1247,"source_url":1248,"license_code":506,"credit_html":1249,"title":1250,"description":1251,"author":1252,"original_width":1253,"original_height":1254},82823,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=21137851","Mariuszjbie, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=21137851\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agat, wrocław.jpg","Agate from Nowy Kościół","Mariuszjbie",1989,1785,{"id":1256,"source_url":1257,"license_code":506,"credit_html":1258,"title":1259,"description":1260,"author":595,"original_width":1115,"original_height":1261},82824,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=24623477","Lech Darski, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=24623477\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Buchanan Thunderegg, Oregon, USA.jpg","Agat – Rancho Buchanan, Oregon. USA.",800,{"id":1263,"source_url":1264,"license_code":404,"credit_html":1265,"title":1266,"description":1267,"author":1268,"original_width":776,"original_height":1269},82827,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=64269972","Daderot, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=64269972\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate - Naturhistorisches Museum Nürnberg - Nuremberg, Germany - DSC04187.jpg","Exhibit in the Naturhistorisches Museum Nürnberg - Nuremberg, Germany.","Daderot",4705,{"id":1271,"source_url":1272,"license_code":358,"credit_html":1273,"title":1274,"description":1275,"author":595,"original_width":1276,"original_height":1277},82828,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=68093670","Lech Darski, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=68093670\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agat Thunderegg x 2 - Richardson Ranch (Priday Ranch), Madras, Jefferson Co.jpg","Agat Thunderegg x 2 - Richardson Ranch (Priday Ranch), Madras, Jefferson Co.",4526,3017,{"id":1279,"source_url":1280,"license_code":516,"credit_html":1281,"title":1282,"description":1283,"author":520,"original_width":1284,"original_height":1285},82829,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974878","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=82974878\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Agate nodule (Succor Creek Claim, Harney County, Oregon, USA) (34670752811).jpg","\u003Cp>Agate nodule (\"Thunder Egg\") from Oregon, USA.\n\u003C\u002Fp>\u003Cp>\"Agate\" is a rockhound\u002Fcollector term for cavities in rocks (usually sedimentary rocks such as limestone or igneous rocks such as basalt) that have been partially or completely filled with irregularly concentric layers of microcrystalline, fibrous quartz (chalcedony - SiO2).  Agate is quartz.\n\u003C\u002Fp>\u003Cp>\"Thunder eggs\" are agate-filled masses that fill former cavities in rocks (see Colburn, 2004 for more info.).\n\u003C\u002Fp>\u003Cp>Locality: Succor Creek Claim, Harney County, Oregon, USA\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Reference cited:\n\u003C\u002Fp>\nColburn (2004) - The Formation of Thundereggs (Lithophysae).  493 pp. (<a href=\"\u003Ca rel=\"nofollow\" class=\"external free\" href=\"http:\u002F\u002Fwww.cvmineralclub.org\u002FMAIN\u002FPages\u002FMembers\">http:\u002F\u002Fwww.cvmineralclub.org\u002FMAIN\u002FPages\u002FMembers\u003C\u002Fa> Articles\u002FJack Marcy\u002FThe Formation of Thundereggs-Revised 2004.pdf\" rel=\"nofollow\">www.cvmineralclub.org\u002FMAIN\u002FPages\u002FMembers%20Articles\u002FJack%...<\u002Fa>) (This long document may take a little while to load on your computer.)",3387,2144,{"id":1287,"source_url":1288,"license_code":358,"credit_html":1289,"title":1290,"description":1291,"author":1212,"original_width":1292,"original_height":1293},82830,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=84817844","Hannes Grobe, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=84817844\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Achat-geschiebe hg.jpg","Agate in Rhyolithe",2134,2330,{"id":1295,"source_url":1296,"license_code":506,"credit_html":1297,"title":1298,"description":1260,"author":595,"original_width":1299,"original_height":566},82831,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=88536485","Lech Darski, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=88536485\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Detail, Buchanan Thunderegg, Oregon, USA (cropped).jpg",486,{"id":1301,"source_url":1302,"license_code":516,"credit_html":1303,"title":1304,"description":1305,"author":520,"original_width":1306,"original_height":1307},82832,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=88547437","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=88547437\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Detail, Quartz-agate nodule (Killer Green Claim, Ochoco Mountains, Prineville, Oregon, USA) (33993292453) (cropped).jpg","\u003Cp>Quartz-agate nodule (\"Thunder Egg\") from Oregon, USA.\n\u003C\u002Fp>\u003Cp>\"Agate\" is a rockhound\u002Fcollector term for cavities in rocks (usually sedimentary rocks such as limestone or igneous rocks such as basalt) that have been partially or completely filled with irregularly concentric layers of microcrystalline, fibrous quartz (chalcedony - SiO2).  Agate is quartz.\n\u003C\u002Fp>\u003Cp>\"Thunder eggs\" are agate-filled masses that fill former cavities in rocks (see Colburn, 2004 for more info.).\n\u003C\u002Fp>\u003Cp>Locality: Killer Green Claim, near Prineville, Ochoco Mountains, central Oregon, USA)\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Reference cited:\n\u003C\u002Fp>\nColburn (2004) - The Formation of Thundereggs (Lithophysae).  493 pp. (<a href=\"\u003Ca rel=\"nofollow\" class=\"external free\" href=\"http:\u002F\u002Fwww.cvmineralclub.org\u002FMAIN\u002FPages\u002FMembers\">http:\u002F\u002Fwww.cvmineralclub.org\u002FMAIN\u002FPages\u002FMembers\u003C\u002Fa> Articles\u002FJack Marcy\u002FThe Formation of Thundereggs-Revised 2004.pdf\" rel=\"nofollow\">www.cvmineralclub.org\u002FMAIN\u002FPages\u002FMembers%20Articles\u002FJack%...<\u002Fa>) (This long document may take a little while to load on your computer.)",1332,1067,[],[1310,1311,1312,1313,1314,1315,1316,1317,1318,1319,1320,1321,1322,1323,1324,1325],"Achat","Achates","Achates vix pellucida","Agaat","Agat","Agata","Agata-diasporo","Agate grossière","Agate orientale","Agate périgone","Agate rubanée","Agate Versiclore","Agate zonaire","Agathe vixpellucida nebulosa colgriseo ore mixta","Akaatti","Oriental Agate",[],{"history":1328,"applications":1332},{"markdown":1329,"model_version":1330,"prompt_version":1331,"reviewed_at":8},"People had been working agate for thousands of years before anyone wrote its name down. Knives and arrowheads chipped from moss agate — a translucent variety threaded with dark dendritic markings — appear at Natufian sites in the Levant as early as 10000 BCE[1]. Worked artefacts from around 7000 BCE turn up in Mongolia[1]. Sumerian jewellery dating to about 2500 BCE includes polished agate beads[1]. Ancient Egyptians, Mycenaeans, and Romans all wore agate set into rings, strung as beads, and carved into cameos and seal stones[1].\n\nThe first written description came from the Greek philosopher Theophrastus around 350 BCE. He named the stone after the River Achates in southwestern Sicily, where it was abundant[2]. Pliny the Elder later repeated the same naming story in his *Natural History*[2]. The link is so old that no one can now say which gave its name to the other — etymologists suspect the river was named after the mineral, not the other way around[3]. The Latin *achātēs* travelled west into the Anglo-Norman French *agathe*, and from there into English[4].\n\n### The Idar-Oberstein cutting industry\n\nBy around 1375 CE, the German town of Idar-Oberstein had built an industry around agate, working local deposits in the surrounding hills[5]. For five centuries its cutters lived on what the nearby streams and quarries gave them. Then, around 1900, the local deposits thinned out just as vast new agate fields opened in Brazil and Uruguay[5][6]. The town did not collapse; it pivoted. Idar-Oberstein began importing Brazilian agate as ship's ballast — heavy stones loaded into empty hulls on the return voyage, then sold to the waiting cutters[5]. The town remained the world's agate-cutting capital, on raw material from another continent.\n\nThe 19th century added a chemical chapter to the trade. The classical methods of staining agate were developed in Idar-Oberstein in the early 19th century[7]. Polished slices were soaked for several days in an inorganic dye or sugar solution, depending on the desired colour[7]. Organic aniline dyes derived from coal tar followed later in the century, opening up pinks and purples that no natural agate offers[7]. Most commercial agate sold today has been stained in some form[8].","claude-opus-4-7","1.7.0",{"markdown":1333,"model_version":1330,"prompt_version":1331,"reviewed_at":8},"Most agate worked today is decorative. Its banded patterns, hardness, and high polish make it a staple of the lapidary trade — cabochons, beads, pendants, earrings, bracelets, carvings, and ornamental displays[1]. The bulk of commercial material is dyed, stained in inorganic solutions or aniline colours to lift the dull grey stone into vivid bands[2].\n\nThe narrower industrial uses exploit three properties of the same mineral: its hardness, its ability to hold a high polish, and its resistance to chemical attack[3].\n\n**Agate mortars and pestles** remain a standard tool in chemistry and pharmacology labs for grinding small samples of reagents and pharmaceuticals[3]. The stone is hard enough to crush most materials and inert enough to leave the powder chemically untouched.\\\nPrecision laboratory balances have long used agate for **bearings and knife edges**[3]. These are small wear surfaces that need to stay hard, smooth, and dimensionally stable over many years of use."]