Crystopedia
IMA mineral species

Talmessite

Ca₂Mg(AsO₄)₂·2H₂O

Arsenate mineral.

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Talmessite specimen
Talmessite-283008.jpg · Wikimedia Commons (see file page for author & license)

Properties

Chemical formulaCa₂Mg(AsO₄)₂·2H₂O
ElementsCa, Mg, As, O, H
Crystal system—
Mohs hardness5
Density—
Streakwhite
Color—
IMA symbolTlm
Nickel–Strunz class8.CG.05

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

🌍 Where it's found

Type locality (where it was first described): Talmessi mine, Iran

  • 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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