Shattuckite

Shattuckite

Shattuckite from the type locality in Bisbee. Size: 6.0×4.9×2.9 cm.
General
Category Inosilicate
Formula
(repeating unit)
Cu5(SiO3)4(OH)2
Strunz classification 9.DB.40
Crystal system Orthorhombic
Crystal class Dipyramidal (mmm)
H-M symbol: (2/m 2/m 2/m)
Space group Pcab
Identification
Color Dark and light blue, turquoise
Crystal habit Commonly spherulitic aggregates of acicular crystals
Cleavage perfect along [010] and [100]
Fracture uneven
Mohs scale hardness 3.5
Luster Dull to silky
Streak Blue
Diaphaneity Translucent to opaque
Specific gravity 4.1 (rather heavy for a non-metallic mineral)
Optical properties Biaxial (+)
Refractive index nα = 1.753, nβ = 1.782, nγ = 1.815
Pleochroism X = very pale blue; Y = pale blue; Z = deep blue
References [1][2][3]

Shattuckite is a copper silicate hydroxide mineral with formula Cu5(SiO3)4(OH)2. It crystallizes in the orthorhombic – dipyramidal crystal system and usually occurs in a granular massive form and also as fibrous acicular crystals. It is closely allied to plancheite in structure and appearance.

Shattuckite is a relatively rare copper silicate mineral. It was first discovered in 1915 in the copper mines of Bisbee, Arizona, specifically the Shattuck Mine (hence the name). It is a secondary mineral that forms from the alteration of other secondary minerals. At the Shattuck Mine, it forms pseudomorphs after malachite. A pseudomorph is an atom by atom replacement of a crystal structure by another crystal structure, but with little alteration of the outward shape of the original crystal.

References

Wikimedia Commons has media related to Shattuckite.
  1. Shattuckite. Webmineral.com. Retrieved on 2011-10-10.
  2. Shattuckite. Mindat.org (2011-09-08). Retrieved on 2011-10-10.
  3. Shattuckite. Handbook of Mineralogy. (PDF) . Retrieved on 2011-10-10.


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