Where it forms, where it's found
- Geological setting
Granitic pegmatite.
- Type locality
- Szklarska Poręba Huta granite quarry
- Szklarska Poręba
- Karkonosze County
- Lower Silesian Voivodeship
- Poland
50.8269°, 15.4946°
2recorded occurrences
Physical
- Hardness
- 1Talc
- 2Gypsum
- 3Calcite
- 4Fluorite
- 5Apatite
- 6Orthoclase
- 7Quartz
- 8Topaz
- 9Corundum
- 10Diamond
- Transparency
- Transparent
- Colour
- Colourless to rarely greenish-grey
- Density
- 3.737 g/cm³
Optical
- Optical type
- Biaxial
- Birefringence
- Low, but the first order of the interference colour spectrum, is leather brown and ink blue to grey-blue.
- Pleochroism
- Visible
- Dispersion
- High
- Notes
Under plane polarized light, the crystals are uncoloured to yellowish. The refractive index is between 1.887 (hydroandradite) and 1.55 (Canada balsam). mean refractive index of ~1.727 calculated from the Gladstone-Dale relation
Crystallography
- Cell parameters
- a = 10.028(1) Å · b = 8.408(1) Å · c = 13.339(2) Å
- Cell angles
- α = 90.01(1) ° · β = 109.10(1) ° · γ = 90.00(1) °
- Ratio a:b:c
- 1 : 0.838 : 1.330
- Z
- 4
- Twinning
Polysynthetic twinning.
- Type-locality form
Mixed kristiansenite-silesiaite crystals with maximum sizes of ~350 × 100 μm. Silesiaite occurs in the form of Fe-dominant bands, usually reaching only a few micrometers in thickness.
- Comment
Space group is C1
Chemical composition
Synonyms
- IMA2017-064
- Silesiaiet
In other languages
- German
- IMA 2017-064 · Silesiait
Classification
Strunz
10th ed.9.BC.30
- 9SilicatesClass
- 9.BSorosilicatesDivision
- 9.BCSi2O7 groups, without non-tetrahedral anions; cations in octahedral [6] and greater coordinationGroup
- 9.BC.30SilesiaiteSpecies
Group, growth & confusion
Literature, links & citation
Citations
- 2017Hålenius, U., Hatert, F., Pasero, M., Mills, S. J. (2017) New minerals and nomenclature modifications approved in 2017, CNMNC Newsletter No 40. Mineralogical Magazine, 81 (6) 1577-1581 doi:10.1180/minmag.2017.081.096DOI: 10.1180/minmag.2017.081.096
- 2021Cepedal, Antonia, Fuertes-Fuente, Mercedes, Martin-Izard, Agustín (2021) Occurrence of silesiaite, a new calcium–iron–tin sorosilicate in the calcic skarn of El Valle-Boinás, Asturias, Spain. European Journal of Mineralogy, 33 (2) 165-174 doi:10.5194/ejm-33-165-2021 DOI: 10.5194/ejm-33-165-2021
- 2022(2022) Silesiaite. Handbook of Mineralogy. Mineralogical Society of America
- 2022Miyawaki, Ritsuro, Hatert, Frédéric, Pasero, Marco, Mills, Stuart J. (2022) IMA Commission on New Minerals, Nomenclature and Classification (CNMNC) – Newsletter 70. European Journal of Mineralogy, 34 (6) 591-601 doi:10.5194/ejm-34-591-2022 DOI: 10.5194/ejm-34-591-2022
- 2023Pieczka, Adam, Zelek-Pogudz, Sylwia, Gołębiowska, Bożena, Stadnicka, Katarzyna M., Kristiansen, Roy (2023) Silesiaite, ideally Ca2Fe3+Sn(Si2O7)(Si2O6OH), a new species in the kristiansenite group: crystal chemistry and structure of holotype silesiaite from Szklarska Poręba, Poland, and Sc-free silesiaite from Häiviäntien, Finland. Mineralogical Magazine, 87 (2) 271-283 doi:10.1180/mgm.2023.5DOI: 10.1180/mgm.2023.5
Cite this entry
@misc{mineral2026,
author = {Mineral Index editorial board},
title = {Silesiaite — Mineral Index},
year = {2026},
url = {https://mineralindex.org/minerals/silesiaite-52572},
note = {Accessed 2026-05-11}
}