Mottramite
PbCu(VO4)(OH)IMA symbol: Mottgrandfathered
Mottramite is a phosphate, arsenate, or vanadate mineral with the formula PbCu(VO4)(OH), crystallizing in the orthorhombic system. It has a Mohs hardness of 3, typically black or yellow in color, with a resinous luster, a specific gravity of 5.894. Its streak is yellow.
Photos
Crystallography
| Crystal system | orthorhombic crystal systemWikidata (CC0) |
|---|---|
| Space group | P n m a |
| Cell (Å, °) | a = 7.667, b = 6.053, c = 9.316; α = 90, β = 90, γ = 90 |
| Cell volume | 432.34 ų, Z = 4 |
| Axial ratios | 1.2666:1:1.5391calculated from COD 9004394 |
| Source structure | COD 9004394 (The Canadian Mineralogist, 1995) — 1 of 3 structures |
Powder X-ray diffraction (calculated)
| d (Å) | 3.239 | 5.076 | 2.599 | 2.878 | 2.695 | 2.659 |
|---|---|---|---|---|---|---|
| I/I₀ | 100 | 61.5 | 59.2 | 57.6 | 44.4 | 44.1 |
xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 9004394; idealized occupancies, no preferred orientation.
Physical properties
| Density (calculated) | 6.187 g/cm³calculated from COD 9004394 |
|---|---|
| Hardness (Mohs) | 3single sourceDana, System of Mineralogy, 6th ed. (1892) |
| Specific gravity | 5.894 g/cm3corroboratedDana, System of Mineralogy, 6th ed. (1892) |
| Color | black, yellowsingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Streak | yellowsingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Luster | resinoussingle sourceDana, System of Mineralogy, 6th ed. (1892) |
Chemistry (calculated)
| Molecular weight | 402.69 g/molcalculated from the IMA formula |
|---|---|
| Composition (wt%) | Pb 51.45%, Cu 15.78%, V 12.65%, O 19.87%, H 0.25% |
Classification
| Nickel-Strunz (10th) | 8.BH.40Wikidata (CC0) |
|---|---|
| Nickel-Strunz (9th) | 8.BH.40Wikidata (CC0) |