Cassiterite — Cassiterite
Cassiterite Wikimedia Commons contributor, Wikimedia Commons, Public domain (US)

Mineral · Rutile group

Cassiterite

SnO2

Cassiterite is tin oxide, the black to brown adamantine crystals of Cornwall, Bolivia (Viloco), China and Namibia, often as 'visor' twins. Its great weight, adamantine lustre and pale streak identify it. Cornish cassiterite specimens from the historic mines are collectible for their history; Chinese and Bolivian crystals are the display pieces.

FormulaSnO2
IMA statusgrandfathered
Crystal systemTetragonal
Mohs hardness6–7
GroupRutile group
Type localityNone (known since antiquity)
StreakWhite to brownish
Specific gravity7.0
Reference listIMA List of Minerals (RRUFF) — verify formula and status against the current list

Elsewhere

Cite this article

Stratum Study. "Cassiterite" (Mineral). Stratum Study pack 2026.09, as of 2026-09-19. https://stratum.black/study/minerals/cassiterite. Accessed 2026-09-20.

@misc{stratum-cassiterite,
  title        = {Cassiterite},
  author       = {{Stratum Study}},
  howpublished = {\url{https://stratum.black/study/minerals/cassiterite}},
  year         = {2026},
  note         = {Mineral article, Stratum Study pack 2026.09, as of 2026-09-19; sources: stratum, wikidata, commons. Accessed 2026-09-20.}
}

Citations carry the pack version and the article's as-of date so they resolve to the same text later. The facts themselves belong to the sources listed below; cite those for the science.

Sources for this article: Stratum editorial (Stratum editorial);Wikidata (CC0);Wikimedia Commons (CC-BY-4.0). As of 2026-09-19; Study pack 2026.09. Data reproduced under the licences shown; text in Stratum's own words unless a section names its source.

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