Rammelsbergite

Rammelsbergite is a nickel arsenide mineral with formula NiAs2. It forms metallic silvery to tin white to reddish orthorhombic prismatic crystals, but is usually massive in form. It has a Mohs hardness of 5.5 and a specific gravity of 7.1.It was first described in 1854 from its type locality in the Schneeberg District in Saxony, Germany. It was named after the German chemist and mineralogist, Karl Friedrich August Rammelsberg.
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General Information:
 Chemical Formula:
NiAs2
 Composition:
(Molecular Weight = 208.53 gm)
Nickel 28.14 % Ni
Arsenic 71.86 % As
 Empirical Formula:
NiAs2
 Name Origin:
Named after the German chemist and mineralogist, K. F. Rammelsberg (1812-1899).
Physical Properties:
 Cleavage:
[???] Indistinct
 Color:
tin white or reddish white.
 Density:
7.1
 Diaphaniety:
Opaque
 Habits:
Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline)., Radial - Crystals radiate from a center without producing stellar forms (e.g. stibnite), Massive - Granular - Commo n texture observed in granite and other
 Hardness:
5.5 - Knife Blade
 Luminescence:
None.
 Luster:
Metallic
 Streak:
black
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