Paramelaconite
| Paramelaconite | |
|---|---|
Paramelaconite from the Copper Queen Mine, Cochise County, Arizona, USA | |
| General | |
| Category | Oxide mineral |
| Formula | CuI 2CuII 2O3 (or Cu4O3) |
| IMA symbol | Pml |
| Strunz classification | 4.AA.15 |
| Dana classification | 4.6.4.1 |
| Crystal system | Tetragonal |
| Crystal class | Ditetragonal dipyramidal (4/mmm) H-M group: (4/m 2/m 2/m) |
| Space group | I41/amd {I41/a 2/m 2/d} |
| Unit cell | a = 5.837 Å, c = 9.932 Å; Z = 4 |
| Identification | |
| Color | Black to black with a slight purple tint White with pinkish brown tint in reflected light |
| Crystal habit | Occurs as striated prismatic crystals; massive |
| Cleavage | None observed |
| Fracture | Conchoidal |
| Tenacity | Brittle |
| Mohs scale hardness | 4.5 |
| Luster | Sub-adamantine, greasy, sub-metallic |
| Streak | Brown-black |
| Diaphaneity | Opaque |
| Specific gravity | 6.04–6.11 (measured) |
| Optical properties | Uniaxial |
| Pleochroism | Weak |
| Ultraviolet fluorescence | Not fluorescent |
| Solubility | Soluble in HCl and HNO3 |
| References | |
Paramelaconite is a rare, black-colored copper(I,II) oxide mineral with formula CuI
2CuII
2O3 (or Cu4O3). It was discovered in the Copper Queen Mine in Bisbee, Arizona, about 1890. It was described in 1892 and more fully in 1941. Its name is derived from the Greek word for "near" and the similar mineral melaconite, now known as tenorite.