Powellite
Ca(MoO4)IMA symbol: Pwlgrandfathered
Powellite is a sulfate mineral with the formula Ca(MoO4), crystallizing in the tetragonal system. It has a Mohs hardness of 3-5, typically green or yellow in color, with a resinous luster, a specific gravity of 4.526. Cleavage is indistinct.
Photos
Crystallography
| Crystal system | tetragonal crystal systemWikidata (CC0) |
|---|---|
| Space group | I 41/a :2 |
| Cell (Å, °) | a = 5.1801, b = 5.1801, c = 11.301; α = 90, β = 90, γ = 90 |
| Cell volume | 303.245 ų, Z = 4 |
| Axial ratios | 1.0000:1:2.1816calculated from COD 9009634 |
| Source structure | COD 9009634 (Journal of Physics and Chemistry of Solids, 1985) — 1 of 8 structures |
Powder X-ray diffraction (calculated)
| d (Å) | 3.074 | 1.909 | 4.709 | 1.573 | 1.675 | 2.59 |
|---|---|---|---|---|---|---|
| I/I₀ | 100 | 31.2 | 29.6 | 24.4 | 15 | 14.3 |
xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 9009634; idealized occupancies, no preferred orientation.
Physical properties
| Density (calculated) | 4.381 g/cm³calculated from COD 9009634 |
|---|---|
| Hardness (Mohs) | 3-5single sourceDana, System of Mineralogy, 6th ed. (1892) |
| Specific gravity | 4.526 g/cm3corroboratedDana, System of Mineralogy, 6th ed. (1892) |
| Color | green, yellowsingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Luster | resinoussingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Cleavage | indistinctDana, System of Mineralogy, 6th ed. (1892) |
Chemistry (calculated)
| Molecular weight | 200.02 g/molcalculated from the IMA formula |
|---|---|
| Composition (wt%) | Ca 20.04%, Mo 47.97%, O 32% |
Classification
| Nickel-Strunz (10th) | 7.GA.05Wikidata (CC0) |
|---|---|
| Nickel-Strunz (9th) | 7.GA.05Wikidata (CC0) |