| Libethenite | |
|---|---|
Libethenite, Wheal Phoenix, Linkinhorne, Cornwall, England. Size: 5.0 x 4.9 x 2.8 cm. |
|
| General | |
| Category | Phosphate minerals |
| Chemical formula | 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).[2][1]