Molybdite
| Molybdite | |
|---|---|
| Molybdite on molybdenite from the Questa Molybdenum Mine (size: 11.0 x 6.7 x 4.1 cm) | |
| General | |
| Category | Minerals | 
| Formula | MoO3 | 
| IMA symbol | Myb | 
| Strunz classification | 4.EA.10 | 
| Crystal system | Orthorhombic | 
| Crystal class | Dipyramidal (mmm) H-M symbol: (2/m 2/m 2/m) | 
| Space group | Pbnm | 
| Unit cell | a = 3.96 Å, b = 13.85 Å, c = 3.69 Å; Z = 4 | 
| Identification | |
| Color | Light greenish yellow to nearly colorless | 
| Crystal habit | Flattened needles or thin plates may occur in aggregates | 
| Cleavage | Perfect on {100}, district on {001} | 
| Tenacity | Flexible | 
| Mohs scale hardness | 3 - 4 | 
| Luster | Adamantine | 
| Streak | White | 
| Diaphaneity | Transparent | 
| Specific gravity | 4.72 | 
| Optical properties | Biaxial (+) | 
| Birefringence | High | 
| 2V angle | Large | 
| References | |
Molybdite is the naturally occurring mineral form of molybdenum trioxide MoO3. It occurs as yellow to greenish needles and crystallizes in the orthorhombic crystal system.