Autunite
Ca(UO2)2(PO4)2·10-12H2OIMA symbol: Autgrandfathered
Autunite is a phosphate, arsenate, or vanadate mineral with the formula Ca(UO2)2(PO4)2·10-12H2O, crystallizing in the orthorhombic system. It has a Mohs hardness of 2-2.5, typically yellow in color, with an adamantine or pearly luster, a specific gravity of 8. Its streak is yellow.
Photos
Crystallography
| Crystal system | orthorhombic crystal systemWikidata (CC0) |
|---|---|
| Space group | P n m a |
| Cell (Å, °) | a = 14.0135, b = 20.7121, c = 6.9959; α = 90, β = 90, γ = 90 |
| Cell volume | 2030.55 ų, Z = 4 |
| Axial ratios | 0.6766:1:0.3378calculated from COD 9002888 |
| Source structure | COD 9002888 (American Mineralogist, 2003) |
Powder X-ray diffraction (calculated)
| d (Å) | 10.356 | 4.467 | 3.566 | 4.951 | 3.314 | 3.564 |
|---|---|---|---|---|---|---|
| I/I₀ | 100 | 36.6 | 26.4 | 24.7 | 23.7 | 22.7 |
xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 9002888; idealized occupancies, no preferred orientation.
Physical properties
| Density (calculated) | 3.149 g/cm³calculated from COD 9002888 |
|---|---|
| Hardness (Mohs) | 2-2.5single sourceDana, System of Mineralogy, 6th ed. (1892) |
| Specific gravity | 8 g/cm3single sourceDana, System of Mineralogy, 6th ed. (1892) |
| Color | yellowsingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Streak | yellowsingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Luster | adamantine, pearlysingle sourceDana, System of Mineralogy, 6th ed. (1892) |
Classification
| Nickel-Strunz (10th) | 8.EB.05Wikidata (CC0) |
|---|---|
| Nickel-Strunz (9th) | 8.EB.05Wikidata (CC0) |