Opal-AG

SiO2·nH2O
Also known as
  • Potch Opal
Variety of
Opal-A
Opal-A

Where it forms, where it's found

6recorded occurrences
Source · OpenStreetMap

Physical

Transparency
Transparent · Translucent

Synonyms

  • Potch Opal

Group, growth & confusion

In the same group
13 members

Literature, links & citation

Citations
  1. 1964JONES, J. B., SANDERS, J. V., SEGNIT, E. R. (1964) Structure of Opal. Nature, 204 (4962). 990-991 doi:10.1038/204990a0DOI: 10.1038/204990a0
  2. 1964SANDERS, J. V. (1964) Colour of Precious Opal. Nature, 204 (4964). 1151-1153 doi:10.1038/2041151a0DOI: 10.1038/2041151a0
  3. 1971Jones, J. B., Segnit, E. R. (1971) The nature of opal I. nomenclature and constituent phases. Journal of the Geological Society of Australia, 18 (1) 57-68 doi:10.1080/00167617108728743DOI: 10.1080/00167617108728743
  4. 1975Sanders, J. V. (1975). Microstructure and crystallinity of gem opals. American Mineralogist, 60, 749-757.
  5. 1991Flörke, 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.
Cite this entry
@misc{mineral2026,
  author    = {Mineral Index editorial board},
  title     = {Opal-AG — Mineral Index},
  year      = {2026},
  url       = {https://mineralindex.org/minerals/opal-ag-32187},
  note      = {Accessed 2026-05-11}
}