Scrutinyite
| Scrutinyite | |
|---|---|
| General | |
| Category | Oxide mineral |
| Formula | PbO2 |
| IMA symbol | Sny |
| Strunz classification | 4.DB.20 |
| Crystal system | Orthorhombic |
| Crystal class | Dipyramidal (mmm) H–M Symbol: (2/m 2/m 2/m) |
| Space group | Pbcn |
| Unit cell | a = 4.91 Å, b = 5.95 Å c = 5.43 Å; Z = 4 |
| Identification | |
| Formula mass | 239.20 g/mol |
| Color | Dark reddish brown |
| Crystal habit | Crystalline, platy |
| Cleavage | {100} perfect, {010} imperfect |
| Fracture | Brittle |
| Luster | Sub-metallic |
| Streak | Dark brown |
| Diaphaneity | Transparent to translucent |
| Specific gravity | 9.867 (calculated) |
| Optical properties | Biaxial |
| Refractive index | n > 2 |
| Other characteristics | Non-fluorescent, nonmagnetic |
| References | |
Scrutinyite /ˈskruːtɪni.aɪt/ is a rare oxide mineral and is the alpha crystalline form of lead dioxide (α-PbO2), plattnerite being the other, beta form. The mineral was first reported in 1988 and its name reflects the scrutiny and efforts required to identify it from a very limited amount of available sample material.