Quartz, Epidote and Prehnite Cluster - NBB 198

Measurements:  53 x 40 x 17 mm

Description:  A stunning, delicate cluster of clear quartz, prehnite and epidote crystals on a thin basalt matrix. The epidote group of crystals have some prehnite blades on, and quartz crystals inside. There are also bits of a light green (to us, unknown) mineral (top right image).

Some of the quartz crystals on the edges are damaged. The bottom of matrix has a few stable flaws.

Weight of Specimen:  25.1 g

Chemical Composition:  SiO₂  (quartz)
                                        Ca₂Al₂Si₃O₁₀(OH)₂  (prehnite)                                                              Ca₂Fe³⁺_2.25Al_0.75(SiO₄)₃(OH)  (epidote)   

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

Location:  Brandberg, Namibia.

Specimen Code:  NBB 198

US $ 140.

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