$1,650Median
3Sold (12 mo)
$1,200Last sale
Talmessite specimens for sale
4 for sale · $1,500–$4,500 USD
10 in the gallery
Talmessite is a hydrated calcium-magnesium arsenate with the chemical formula Ca2Mg(AsO4)2·2(H2O). It typically forms colorless to white, or pale green crystals with a vitreous luster and a transparent to translucent appearance. The mineral crystallizes in the triclinic system and commonly displays small prismatic to tabular habits that may be intermixed with acicular or granular aggregates. Its hardness is around 5 on the Mohs scale and it has a modest specific gravity in the 3.2–3.5 range.
- Formula
- Ca2Mg(AsO4)2·2(H2O)
- Classification notes
- Hydrated Phosphates, etc
Key characteristics
- Crystal system
- triclinic
- Mohs hardness
- 5
- Specific gravity
- 3.2–3.5
- Luster
- vitreous
- Transparency
- transparent, translucent
- Color
- colorless, white, green
- Streak
- white
Buy Talmessite specimens
View all 4Where Talmessite is found
Top localities
- Aghbar Mine3 specimens
- Bou Azzer2 specimens
About Talmessite
Notable specimens have been reported from a number of classic European and world deposits, but Morocco, China, and the USA are listed as fruitful sources for Talmmessite in modern collections. Localities in these regions have produced specimens that highlight its delicate transparency and its pale green to colorless color range, often forming in association with other phosphates and arsenates in hydrothermal environments. For collectors, talmessite offers appeal through its rarity, medium hardness, and the potential for well-formed crystals that display clean faces and sharp edges when conditions favor growth. Its hydrated nature can complicate restoration and storage, but well-preserved examples are valued for their understated elegance and scientific interest.
