Prehnite, Quartz, Calcite and Epidote Cluster - NBB 048

Description:  A lovely mixture of prehnite, quartz and calcite, with traces of epidote. The crystals are quite gemmy! 

The bottom photograph shows the bottom of the specimen, with a bit of the matrix. There is also some damage there. The specimen appears to have been attached to the mother rock at two places.

Chemical Composition:  Ca₂Al₂Si₃O₁₀(OH)₂    (prehnite)  
                                    SiO₂  (quartz)  
                                    CaCO₃  (calcite) 
                                    Ca₂Fe³⁺_2.25Al_0.75(SiO₄)₃(OH) (epidote)
                                 
Hardness on Mohs Scale:   (prehnite) 6-6.5
                                       (quartz)  7                                                                                          (calcite)  3
                                       (epidote) 7   

Location:  Brandberg, Namibia

Specimen Code:  NBB 048

US $ 60