Libethenite

Libethenite

Libethenite, Wheal Phoenix, Linkinhorne, Cornwall, England. Size: 5.0 x 4.9 x 2.8 cm.
General
Category Phosphate minerals
Formula
(repeating unit)
Cu2PO4OH
Strunz classification 08.BB.30
Identification
Color Light to dark green, blackish green, olive-green
Crystal habit Globular, druzy, slender prismatic
Crystal system Orthorhombic
Cleavage Indistinct on [100] and [010]
Fracture Irregular, uneven to conchoidal
Tenacity Brittle
Mohs scale hardness 4
Luster Vitreous, greasy
Streak light green
Specific gravity 3.6 - 4, Average = 3.8
Optical properties Biaxial (-)
Refractive index nα = 1.701 - 1.704 nβ = 1.743 - 1.747 nγ = 1.787 - 1.790
References [1][2]

Libethenite is a rare copper phosphate hydroxide mineral. It forms striking, dark green orthorhombic crystals. It was discovered in 1823 in Ľubietová, Slovakia and is named after the German name of that locality (Libethen).[1][2]

References

Detail of gemmy, emerald-green, orthorhombic libethenite microcrystals on malachite, from the type locality, Ľubietová, Slovakia. See File:Libethenite-258236.jpg for the full specimen.


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