Mineral: Villiaumite
Locality: Koashva Open Pit, Koashva Mountain, Khibiny Massif, Kola Peninsula, Murmanskaja Oblast, Northern Region, Russia
Dimensions: 48x29x18
Description: Dark red villiaumite in a matrix of nepheline-syenite from the Koashva Open Pit on the Kola Peninsula. A relatively rare Halite Group mineral, villiaumite occurs as gangue material deep in foyaite rocks and in miarolitic cavities within nepheline-syenite pegmatites. It forms granular and massive aggregates or imperfect crystals, cubic in appearance, often rounded. The approximate chemical composition of villiaumite is 54.75% Na (sodium) and 45.25% F (fluoride). It is readily soluble in water.
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