Quartz with Schorl - NER 073

Measurements:  50 x 30 x 12 mm

Description:   A quartz crystal, with a piece of quartz attached, has numerous schorl needles on its surface, and some inside, with a few having both ends protruding through adjoining shaft facets.

The main quartz termination has a minute nick, while the lower part has a neat pressure mark. 

Weight of Specimen:  9.8 g

Chemical Composition:  SiO₂  (quartz)   
                                       NaFe²⁺₃Al₆Si₆O₁₈(BO₃)₃(OH)₄  (schorl)
        
Hardness on Mohs Scale:  (quartz)  7      
                                          (schorl)  7.5                                     

Location:  Erongo, Namibia.

Specimen Code:  NER 073