Sperrylite
PtAs2IMA symbol: Spygrandfathered
Sperrylite is a sulfide or sulfosalt mineral with the formula PtAs2, crystallizing in the cubic system. It has a Mohs hardness of 6-7, typically white in color, with a metallic luster, a specific gravity of 10.6. Its streak is black; cleavage is distinct.
Photos
Crystallography
| Crystal system | cubic crystal systemWikidata (CC0) |
|---|---|
| Space group | P a -3 |
| Cell (Å, °) | a = 5.9665, b = 5.9665, c = 5.9665; α = 90, β = 90, γ = 90 |
| Cell volume | 212.402 ų, Z = 4 |
| Axial ratios | 1.0000:1:1.0000calculated from COD 9012408 |
| Source structure | COD 9012408 (Canadian Journal of Chemistry, 1968) — 1 of 4 structures |
Powder X-ray diffraction (calculated)
| d (Å) | 1.799 | 2.983 | 3.445 | 2.109 | 1.148 | 2.668 |
|---|---|---|---|---|---|---|
| I/I₀ | 100 | 78.1 | 57 | 51.9 | 35.1 | 29.1 |
xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 9012408; idealized occupancies, no preferred orientation.
Physical properties
| Density (calculated) | 10.786 g/cm³calculated from COD 9012408 |
|---|---|
| Hardness (Mohs) | 6-7single sourceDana, System of Mineralogy, 6th ed. (1892) |
| Specific gravity | 10.6 g/cm3corroboratedFord, Dana's Textbook of Mineralogy, 3rd ed. (1922) |
| Color | whitesingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Streak | blacksingle sourceWikidata (CC0) blacksingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Luster | metallicsingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Cleavage | distinctsingle sourceFord, Dana's Textbook of Mineralogy, 3rd ed. (1922) |
Chemistry (calculated)
| Molecular weight | 344.93 g/molcalculated from the IMA formula |
|---|---|
| Composition (wt%) | Pt 56.56%, As 43.44% |
Classification
| Nickel-Strunz (10th) | 2.EB.05aWikidata (CC0) |
|---|---|
| Nickel-Strunz (9th) | 2.EB.05aWikidata (CC0) |