Quartz, Prehnite, Epidote and Analcime Druse on Basalt Matrix - NBB 212

Measurements:  53 x 35 x 21 mm

Description:  Clear quartz crystals, mainly gemmy, (up to about 7 mm long) with prehnite crystals, small epidote crystal clusters (up to about 3 mm wide) and small, clear analcime crystals and an odd piece of calcite, grouped together on basalt matrix.

The specimen has minimal damage and displays well. The photograph (bottom, right) shows the bottom of the specimen.

Weight of Specimen:  30.4 g

Chemical Composition:  SiO₂  (quartz) 
                                       Ca₂Al₂Si₃O₁₀(OH)₂   (prehnite)                                                              Ca₂Fe³⁺_2.25Al_0.75(SiO₄)₃(OH)  (epidote) 
                                       NaAl(Si₂O₆)•(H₂O)  (analcime)                                                               CaCO₃  (calcite)  

Hardness on Mohs Scale:  (quartz)  7
                                          (prehnite) 6-6.5
                                          (epidote)  7
                                          (analcime)  5
                                          (calcite)  3 

Location:  Brandberg, Namibia.

Specimen Code:  NBB 212

US $ 75

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