Schorl and Feldspar Crystal Group – NERS 010

Measurements:  42 x 40 x 32 mm

Description:  A group of schorl (variety foitite) and feldspar crystals. The large feldspar crystal has bits of minute mica on its surfaces. 

The specimen has some pressure marks and nicks.

Weight of Specimen:  47.5 g

Chemical Composition:  NaFe²⁺₃Al₆Si₆O₁₈(BO₃)₃(OH)₄  (schorl)
                                       KAlSi₃O₈  (feldspar) 
                                        KAl₂(Si₃Al)O₁₀(OH_,F)₂  (muscovite /mica) 

Hardness on Mohs Scale:  (schorl) 7.5
                                          (feldspar) 6 - 6.5
                                           (muscovite / mica) 2-2.5

Location:  Erongo Mountains, Erongo Region, Namibia.

Specimen Code:  NERS 010

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