General Information:
Chemical Formula:
Na4K3(Fe++,Mn++,Ti)2Si8O20(OH)4·4(H2O)
Environment:
In hyperagpaitic pegmatites.
IMA Status:
Approved IMA
Locality:
Mt. Koashva, SE part of the Khibina alkaline massif, Kola Peninsula, Russia.
Name Origin:
Named after Prof. Vadim Viktorovich Ershov (1939-1989) of the Moscow Mining Institute.
Physical Properties:
Cleavage:
[100] Perfect, [010] Perfect
Color:
olive green, brownish green, or yellowish green.
Density:
2.75 - 2.69, Average = 2.72
Diaphaniety:
Transparent
Habits:
Anhedral Grains - Granular minerals without the expression of crystal shapes, Fibrous - Crystals made up of fibers.,
Hardness:
2.5-3 - Finger Nail-Calcite
Luminescence:
Non-fluorescent.
Luster:
Vitreous (Glassy)
Streak:
white
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