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Melonite

Melonite
Melonite-Calaverite-219105.jpg
Melonite after calaverite, on quartz. Cresson mine, Cripple Creek, Colorado. Size: 1.3 × 0.9 × 0.4 cm.
General
Category Sulfide minerals
Formula
(repeating unit)
NiTe2
Strunz classification 2.EA.20
Dana classification 02.12.14.01
Crystal system Trigonal
Crystal class Hexagonal scalenohedral (3m)
H-M symbol: (3 2/m)
Space group P3m1
Unit cell a = 3.84 Å, c = 5.26 Å; Z = 1
Identification
Formula mass 313.89 g/mol
Color White, reddish white
Crystal habit Crystalline, foliated, granular
Cleavage {0001} Perfect
Fracture Brittle
Mohs scale hardness 1–1.5
Luster Metallic
Streak Dark gray
Diaphaneity Opaque
Specific gravity 7.72
Density 7.3
Ultraviolet fluorescence None
References

Melonite is a telluride of nickel; it is a metallic mineral. Its chemical formula is NiTe2. It is opaque and white to reddish-white in color, oxidizing in air to a brown tarnish.

It was first described from the Melones and Stanislaus mine in Calaveras County, California in 1866, by Frederick Augustus Genth.

Melonite occurs as trigonal crystals, which cleave in a (0001) direction. It has a specific gravity of 7.72 and a hardness of 1–1.5 (very soft).



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