Jarosite
KFe3+3(SO4)2(OH)6IMA symbol: Jrsredefined
Jarosite is a sulfate mineral with the formula KFe3+3(SO4)2(OH)6, crystallizing in the hexagonal system. It has a Mohs hardness of 2, typically brown or yellow in color, with an adamantine or dull luster, a specific gravity of 3.15-3.26. Its streak is yellow.
Photos
Crystallography
| Crystal system | hexagonal crystal systemWikidata (CC0) |
|---|---|
| Space group | R -3 m :H |
| Cell (Å, °) | a = 7.2913, b = 7.2913, c = 17.1744; α = 90, β = 90, γ = 120 |
| Cell volume | 790.719 ų, Z = 3 |
| Axial ratios | 1.0000:1:2.3555calculated from COD 9016962 |
| Source structure | COD 9016962 (American Mineralogist, 2013) — 1 of 20 structures |
Powder X-ray diffraction (calculated)
| d (Å) | 3.075 | 3.105 | 5.087 | 1.823 | 1.976 | 2.287 |
|---|---|---|---|---|---|---|
| I/I₀ | 100 | 58.7 | 50.3 | 33.4 | 32.5 | 32.4 |
xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 9016962; idealized occupancies, no preferred orientation.
Physical properties
| Density (calculated) | 3.117 g/cm³calculated from COD 9016962 |
|---|---|
| Hardness (Mohs) | 2single sourceDana, System of Mineralogy, 6th ed. (1892) |
| Specific gravity | 3.15-3.26 g/cm3corroboratedDana, System of Mineralogy, 6th ed. (1892) |
| Color | brown, yellowsingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Streak | yellowsingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Luster | adamantine, dull, vitreoussingle sourceDana, System of Mineralogy, 6th ed. (1892) |
Classification
| Nickel-Strunz (10th) | 7.BC.10Wikidata (CC0) |
|---|---|
| Nickel-Strunz (9th) | 7.BC.10Wikidata (CC0) |