Autunite | |
Chemical Formula |
Ca(UO2)2(PO4)2·10-12H2O |
Species |
Phosphates |
Crystal System |
Orthorhombic |
Mohs Scale |
2 |
Specific Gravity |
3.1-3.2 |
Color |
Lemon-yellow to sulfur-yellow, greenish yellow to pale green; may be dark green to greenish black |
Streak |
Pale yellow |
Luster |
Sub-Vitreous, Resinous, Waxy, Pearly |
Refractive Index |
n = 1.553 - 1.555 n = 1.575 n = 1.577 - 1.578 n = 1.575 n = 1.572 |
Diaphaneity |
Transparent, Translucent |
Cleavage |
PerfectPerfect on , indistinct on |
Fracture |
Micaceous |
Crystal Habit:Tabular crystals, foliated or scaly aggregates, and in crusts | |
Geological Setting:In the oxidation zone of uranium bearing rocks, including sandstones, hydrothermal veins, and granitic pegmatites. |