Mineral description : Grünerite

Radiating suns of pale grünerite crystals. From McLeod Mine, Ontario, USA. (Got it by trade.)

Mineral class	Silicates : Inosilicates : Cummingtonite anthophyllite group
Chemical formula	(Fe,Mg)7Si8O22(OH)2
Crystal system	Monoclinic
Habitus	Fibric to lamellar, often in radiating aggregates.
Cleavage	Good in two directions (125° amphibol cleavage), fracture uneven.
Hardness	5 - 6
Density	3.44 - 3.60
Color	Brownish, dark green or gray, translucent to opaque.
Streak
Luster	Silky.
Description
Occurance	In contact methamorphic rocks.
Associates
Notes	Type locality : Collobrières, Var, France.
Locations	A less common amphibole. Stora Uttervik, Tunaberg. Mansjöberg, Los. Hällefors silver mine.

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