Quartz and Calcite on Chalcedony – NBB 203

Measurements:  69 x 49 x 30 mm                  

Description:  A delicate and very interesting specimen consisting of 'bladed' clear quartz crystals, calcite crystals (some with a coating of iron oxide) and a brownish (unknown to us) botryoidal mineral that covers most of the matrix top. 

The specimen has not been cleaned, due to its delicate nature and looks far better when viewed through a loupe. The only damage appears to be to the specimen's edges.             

Weight of Specimen:  96.4 g

Chemical Composition:  SiO₂  (quartz)
                                  CaCO₃  (calcite)

Hardness on Mohs Scale:  (quartz)  7 
                                          (calcite)  3

Location:  Brandberg, Namibia.

Specimen Code:  NBB 203