Chemistry:Teineite

Teineite
General
Category	Mineral
Formula (repeating unit)	Cu(TeO3)·2 H2O
Strunz classification	4.JM.20
Dana classification	34.2.2.2
Crystal system	Orthorhombic
Crystal class	Disphenoidal (222) H-M symbol: (2 2 2)
Space group	P212121
Unit cell	a = 6.63, b = 9.61 c = 7.43 [Å]; Z = 4
Identification
Color	Sky-blue, cobalt-blue, bluish gray, bright blue to greenish blue in transmitted light.
Crystal habit	Prismatic or flattened crystals, Sometimes as crusts or aggregates
Cleavage	Distinct
Fracture	Brittle
Tenacity	Brittle
Mohs scale hardness	2.5
|re|er}}	Vitreous, dull
Streak	Light blue
Diaphaneity	Semitransparent
Specific gravity	3.8
Optical properties	Biaxial (−)
Birefringence	δ = 0.024
Pleochroism	Various shades of blue
2V angle	36o
Fusibility	Fusible, gives a black bead
Solubility	Insoluble
Common impurities	Sulfur
References

Teineite is a tellurite mineral with the formula Cu(TeO₃). 2 H₂O. It has a Mohs hardness of 2.5 and it comes in many different shades of blue, ranging from cerulean blue to bluish-gray. The mineral millsite has the same chemical composition, but crystallizes in the monoclinic system, while teineite crystallizes in the orthorhombic system.

Occurrence

Teineite was first identified in the Teine mine, Sapporo, Hokkaido, Japan , where the name of this mineral originates. It occurs in veins where copper- and tellurium-bearing sulfides were oxidized and is often associated with tellurite, tellurium, pyrite, tetrahedrite, sphalerite, azurite, malachite, quartz, baryte, hessite, galena, bornite, cerussite, chlorargyrite, quetzalcoatlite, cuprite and graemite. It has also been found in other places, including other mines in Japan, several mines in the United States and mines in Mexico, Belgium, Russia and Norway .

See also

• List of minerals