Boleite
| Boleite | |
|---|---|
| General | |
| Category | Halide mineral |
| Formula | KPb26Ag9Cu24(OH)48Cl62 |
| IMA symbol | Bol |
| Strunz classification | 3.DB.15 |
| Crystal system | Isometric |
| Crystal class | Hexoctahedral (m3m) H-M symbol: (4/m 3 2/m) |
| Space group | Pm3m |
| Unit cell | a = 15.29 Å; Z = 1 |
| Identification | |
| Color | Deep Prussian blue to indigo |
| Crystal habit | Cubic crystals |
| Cleavage | [001] perfect |
| Fracture | Uneven |
| Mohs scale hardness | 3.0 – 3.5 |
| Luster | Vitreous to pearly |
| Streak | Greenish blue |
| Diaphaneity | Translucent |
| Specific gravity | 5.054 |
| Optical properties | Isotropic |
| Refractive index | n = 2.05 |
| Other characteristics | Radioactive 0.36% (K) |
| References | |
Boleite is a complex halide mineral with formula: KPb26Ag9Cu24(OH)48Cl62. It was first described in 1891 as an oxychloride mineral. It is an isometric mineral which forms in deep-blue cubes. There are numerous minerals related to boleite, such as pseudoboleite, cumengite, and diaboleite, and these all have the same complex crystal structure. They all contain bright-blue cubic forms and are formed in altered zones of lead and copper deposits, produced during the reaction of chloride bearing solutions with primary sulfide minerals.