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Ajoite

Ajoite
Ajoite-275005.jpg
Ajoite from Arizona (size: 2.4×2.4×2.0 cm)
General
Category Silicate mineral
Formula
(repeating unit)
(Na,K)Cu7AlSi9O24(OH)6.3H2O
Strunz classification 9.EA.70 (10 ed)
8/D.07-10 (8 ed)
Dana classification 78.05.01.011
Crystal system Triclinic
Crystal class Pinacoidal (1)
(same H-M symbol)
Space group P1
Unit cell a = 13.63, b = 14.5
c = 13.62 [Å]; α = 107.16°
β = 105.45°, γ = 110.57°; Z = 1
Identification
Color Bluish green
Crystal habit Sprays of bladed prismatic crystals
Cleavage Perfect on {010}
Mohs scale hardness
Luster Vitreous
Streak Greenish white
Diaphaneity Translucent
Specific gravity 2.96
Optical properties Biaxial (+)
Refractive index nα = 1.550, nβ = 1.583, nγ = 1.641
Birefringence δ = 0.091
Pleochroism X: very light bluish green; Y and Z: brilliant bluish green
2V angle Measured: 68° to 80°
Solubility Decomposed by acids
References

Ajoite is a hydrated sodium potassium copper aluminium silicate hydroxide mineral. Ajoite has the chemical formula , and minor Mn, Fe and Ca are usually also present in the structure. Ajoite is used as a minor ore of copper.


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Wikipedia

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