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Anorthite

Origin Of  Name:
From the Greek word ‘oblique’ in reference to anorthite’s crystal shape.
Copyright: geology.today

Physical properties:- 
Hardness: 6 to 6.5
Cleavage: perfect(001), good(010), poor(110)
Specific gravity: 2.76
Fracture: Uneven
Luster:  vitreous to pearly
Transparency: translucent
Colour: white, gray, 
Streak: white
Crystal system: triclinic

Occurance: 
Anorthite is a rare compositional variety of plagioclase. It occurs in mafic igneous rock.
It also occurs in metamorphic rock of granulite facies, in metamorphosed carbonate rocks,  and corundum deposits.
  
Uses:  
it is used in the manufacture of glass and ceramics.

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