Calcite Crystals and (?)Mottramite on Matrix - NTS 048

Measurements:  95 x 80 x 25 mm

Description:  Clear calcite crystals up to 10 mm on edge, sit on a (to us, unknown) rock matrix, with a partial coating of (?)mottramite. There are a few tiny patches of duftite on the matrix.

There is some damage to a few of the crystals towards the edges of the specimen.

Weight of Specimen:  188.4 g

Chemical Composition:  CaCO₃  (calcite)
                                       PbCu(VO₄)(OH)  (mottramite)   
                                       PbCu(AsO₄)(OH)  (duftite)  

Hardness on Mohs Scale:  (calcite) 3
                                          (mottramite)  3 - 3½
                                          (duftite)  4½

Location:  Tsumeb, Northern Namibia.

Specimen Code:   NTS 048

US $ 45