Quartz Crystals with Prehnite, Epidote and Calcite on Matrix - NBB 034

Description:  A lovely arrangement of quartz crystals with scores of small prehnite crystals on small epidote and calcite crystals. 

Some of the quartz crystals are up to 19 mm long, and a few are double terminated. There are a few minute specks and threads of hematite visible, as well as a very faint hint of amethyst colouring.

The epidote is in two different colours (perhaps a different mineral?). 

There is very little damage to this specimen.

Chemical Composition:  SiO₂  (quartz)
                              Ca₂Al₂Si₃O₁₀(OH)₂    (prehnite)  
                                    Ca2(Fe³⁺, Al)3(SiO₄)₃(OH)   (epidote)                                                       CaCO₃    (calcite)                         

Hardness on Mohs Scale:  (quartz)  7 
                                      (prehnite)  6-6.5
                                      (epidote) 7      
                                                (calcite)  3    

Location:  Brandberg, Namibia.

Specimen Code:  NBB 034

US $ 120