Crystopedia
IMA mineral species

Brownmillerite

Ca₂(Al,Fe³⁺)₂O₅

Rare calcium aluminium oxide mineral.

RedBrown

Brownmillerite specimen
Brownmillerite-103177.jpg · Wikimedia Commons (see file page for author & license)

Properties

🔷 Orthorhombic
Chemical formulaCa₂(Al,Fe³⁺)₂O₅
ElementsCa, Al, Fe, O
Crystal systemOrthorhombic
Mohs hardness—
Density—
Streak—
Color—
IMA symbolBmlr
Nickel–Strunz class4.AC.10

“—” means no reliable value in Wikidata yet. Check Mindat for full data.

🌍 Where it's found

Type locality (where it was first described): Bellerberg volcano, Germany

  • Type locality
  • Notable source / deposit
  • Country of origin

Marker positions are approximate (region or locality level). Type localities from Wikidata; notable sources curated by Crystopedia.

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