Lorándite
TlAsS2IMA symbol: Lorrenamed
Lorándite is a sulfide or sulfosalt mineral with the formula TlAsS2, crystallizing in the monoclinic system. It has a Mohs hardness of 3-5, typically black, gray or red in color, a specific gravity of 6.3. Its streak is red.
Photos
Crystallography
| Crystal system | monoclinic crystal systemWikidata (CC0) |
|---|---|
| Space group | P 1 21/a 1 |
| Cell (Å, °) | a = 12.296, b = 11.313, c = 6.114; α = 90, β = 104.21, γ = 90 |
| Cell volume | 824.463 ų, Z = 8 |
| Axial ratios | 1.0869:1:0.5404calculated from COD 9011731 |
| Source structure | COD 9011731 (Neues Jahrbuch fur Mineralogie, Abhandlungen, 1995) — 1 of 3 structures |
Powder X-ray diffraction (calculated)
| d (Å) | 3.563 | 3.683 | 2.752 | 2.882 | 3.595 | 3.573 |
|---|---|---|---|---|---|---|
| I/I₀ | 100 | 89.9 | 83.7 | 64.9 | 64.2 | 63.9 |
xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 9011731; idealized occupancies, no preferred orientation.
Physical properties
| Density (calculated) | 5.534 g/cm³calculated from COD 9011731 |
|---|---|
| Hardness (Mohs) | 3-5single sourceFord, Dana's Textbook of Mineralogy, 3rd ed. (1922) |
| Specific gravity | 6.3 g/cm3single sourceFord, Dana's Textbook of Mineralogy, 3rd ed. (1922) |
| Color | black, gray, redsingle sourceFord, Dana's Textbook of Mineralogy, 3rd ed. (1922) |
| Streak | redsingle sourceFord, Dana's Textbook of Mineralogy, 3rd ed. (1922) |
Chemistry (calculated)
| Molecular weight | 343.43 g/molcalculated from the IMA formula |
|---|---|
| Composition (wt%) | Tl 59.51%, As 21.82%, S 18.67% |
Classification
| Nickel-Strunz (10th) | 2.HD.05Wikidata (CC0) |
|---|---|
| Nickel-Strunz (9th) | 2.HD.05Wikidata (CC0) |