Demesmaekerite
| Demesmaekerite | |
|---|---|
 A specimen of demesmaekerite associated with blue chalcomenite crystals | |
| General | |
| Category | Oxide mineral |
| Formula (repeating unit) | Pb2Cu5(UO2)2(SeO3)6(OH)6•2H2O |
| Strunz classification | 4.JJ.20 |
| Crystal system | Triclinic |
| Crystal class | Pinacoidal (1) (same H-M symbol) |
| Space group | P1 |
Demesmaekerite is an uranium mineral with the chemical formula: Pb2Cu5(UO2)2(SeO3)6(OH)6•2H2O.
It is named after the Belgian mineralogist, who worked at the Musonoi Mine, Gaston Demesmaeker (born 1911).[1] It is a secondary mineral which contains lead, copper and (the rarer in minerals) selenium, it is a bottle green to brown/yellow colour, its crystal habit changes from one form to another form depending on where it is found. It has a Mohs hardness of about 2-3.
It can be found alongside other very rare selenium-bearing uranium ores, such as haynesite, guilleminite, marthozite and piretite.[2]