Stannoidite

Stannoidite is a sulfide mineral composed of five chemical elements: copper, iron, zinc, tin and sulfur. Its name originates from Latin stannum (tin) and Greek eides (or Latin oïda meaning "like"). The mineral is found in hydrothermal Cu-Sn deposits.^[2][3]

Stannoidite
Silvery stannoidite crystals from the Akenobe Mine, Yabu City, Honshu Island, Japan, associated with chalcopyrite
General
Category	Sulfide mineral
Formula	Cu6+Cu22+(Fe2+,Zn)3Sn2S12
IMA symbol	Sta[1]
Strunz classification	2.CB.15c
Crystal system	Orthorhombic
Crystal class	Disphenoidal (222) H-M symbol: (2 2 2)
Space group	I222 (No. 23)
Unit cell	a = 10.76 Å, b = 5.4 Å c = 16.09 Å, Z = 2
Identification
Color	Brass brown
Crystal habit	Uniformly indistinguishable crystals forming large masses
Cleavage	None
Fracture	Conchoidal – uneven
Mohs scale hardness	4
Luster	Metallic
Streak	Brown gray
Diaphaneity	Opaque
Specific gravity	4.29
References	[2][3][4]

Stannoidite was first described in 1969 for an occurrence in the Konjo mine, Okayama prefecture, Honshu Island, Japan.^[3]

See also

• Stannite
• Kesterite