Stannite

Stannite

Stannite Fabulosa Mine, Larecaja Province, La Paz Department, Bolivia- 2 mm crystals
General
Category Sulfide mineral
Formula
(repeating unit)
Cu2FeSnS4
Strunz classification 02.CB.15a
Crystal symmetry Tetragonal 4 2m
Unit cell a = 5.4432 Å, c = 10.7299 Å; Z=2
Identification
Color Steel-gray to iron-black, may tarnish blue
Crystal habit Rarely as pseudo-octahedral crystals also massive, granular, and disseminated
Crystal system Tetragonal - Scalenohedral H-M Symbol (42m) Space Group: 42m
Twinning Penetration twins on {102}
Cleavage Indistinct on {110} and {001}
Fracture Uneven
Mohs scale hardness 4
Luster Metallic
Streak Black
Diaphaneity Opaque
Specific gravity 4.3 - 4.5
References [1][2][3]

Stannite is a mineral, a sulfide of copper, iron, and tin. The chemical formula Cu2FeSnS4. Zinc commonly occurs with the iron and trace germanium may be present.[3] Stannite is used as an ore of tin, consisting of approximately 28% tin, 13% iron, 30% copper, 30% sulfur by mass. It is found in tin-bearing, hydrothermal vein deposits occurring with chalcopyrite, sphalerite, tetrahedrite, arsenopyrite, pyrite, cassiterite, and wolframite.[1] Also known as bell metal ore.

The name comes from the Latin for tin: stannum. It was first described in 1797 for an occurrence in Wheal Rock, St. Agnes, Cornwall, England.[3]

See also

References