Smoky Quartz Crystal with Hyalite Opal, on Mica Matrix – NER 008

Measurements:  77 x 57 x 45 mm 

Description:  A dark smoky quartz crystal (44 mm long) with bits of hyalite opal attached to some of its facets, rests on a mount of yellow mica crystals, feldspar, schorl and hyalite opal. 

The specimen is concave underneath (see image bottom, left), and appears to have formed over a large quartz crystal point (and thus bearing its shape), but has since become dislodged from it.

The smoky quartz crystal has a small nick to its termination. The mount has limited damage to the top and sides.

This is a pretty, delicate specimen.

Weight of Specimen:  55.9 g

Chemical Composition:  SiO₂  (quartz)  
                                        SiO2•1.5(H2O)  (opal)
                                        KAl₂(Si₃Al)O₁₀(OH_,F)₂  (muscovite)                                                         KAlSi₃O₈  (feldspar) 

Hardness on Mohs Scale:  (quartz)  7     
                                          (opal)  5.5-6 
                                          (muscovite)  2-2.5
                                          (feldspar)  6 - 6.5
                                          
Location:  Erongo Mountains, Erongo Region, Namibia.

Specimen Code:  NER 008 

US $ 65