Talmessite, (w. Calcite)

Talmessite


Composition:

Ca2Mg(AsO4)2.2H2O

Crystal System : Triclinic
Colours: Pale-yellow
Lustre : Vitreous
Hardness (H) : 5
Specific Gravity (S.G) : 3.2-3.5

 

Distribution

Extremely rare (?)

Occurrence

  • Supergene

Paragenetic and General Notes

Talmessite, confirmed by EDS and XRD, has been reported to occur at Tsumeb by Franz Neuhold (http://www.mindat.org/locentry-617558.html; accessed April 2015).

A specimen in the W.(Bill) Pinch collection has been used to verify the unit cell parameters for this species.