Almandine — Almandine
Almandine Robert M. Lavinsky, Wikimedia Commons, CC BY SA 3.0

Mineral · Garnet group

Almandine

Fe2+3Al2(SiO4)3

Almandine is iron aluminium garnet, the dark red to brown-red dodecahedra in mica schist from Wrangell Island (Alaska), Emerald Creek (Idaho), Madagascar and India, and the source of most 'garnet' sand and abrasive. Large, sharp crystals in schist from Alaska and Norway are cheap and decorative. It is the commonest garnet.

FormulaFe2+3Al2(SiO4)3
IMA statusgrandfathered
Crystal systemCubic
Mohs hardness7–7.5
GroupGarnet group
Type localityNone (Alabanda, Turkey, historical)
StreakWhite
Specific gravity4.3
Reference listIMA List of Minerals (RRUFF) — verify formula and status against the current list

Elsewhere

Cite this article

Stratum Strata. "Almandine" (Mineral). Stratum Strata pack 2026.09, as of 2026-09-21. https://stratum.black/strata/minerals/almandine. Accessed 2026-09-21.

@misc{stratum-almandine,
  title        = {Almandine},
  author       = {{Stratum Strata}},
  howpublished = {\url{https://stratum.black/strata/minerals/almandine}},
  year         = {2026},
  note         = {Mineral article, Stratum Strata pack 2026.09, as of 2026-09-21; sources: stratum, wikidata, commons. Accessed 2026-09-21.}
}

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