aluminite vs natrojarosite

aluminite (mineral) | natrojarosite (mineral)

Images

| aluminite | natrojarosite alternate names | alley stone | native argill | websterite | soda copperas formula | Al_2(SO_4)(OH)_4·7(H_2O) | NaFe^(3+)_3(SO_4)_2(OH)_6 discovery year | 1807 | 1902

| aluminite | natrojarosite density | 1.68 g/cm^3 | 3.1 g/cm^3 transparency | opaque | transparent | translucent birefringence | 0.011 | 0.08 luster | earthy | vitreous Mohs hardness | 3/2 | 3 tenacity | fragile | brittle streak | white | light yellow magnetism | nonmagnetic | nonmagnetic color | white | grayish white | yellow | ochre yellow | ochre brown fracture | earthy | uneven molar mass | 344.2 g/mol | 484.7 g/mol

| aluminite | natrojarosite Strunz ID | VI/D.06-40 | VI/B.11-50 Dana ID | 31.7.4.1 | 30.2.5.2 ICSD number | ICSD2234 |

| aluminite | natrojarosite crystal system | monoclinic | trigonal crystal class | 2/m | 3m unit cell volume | 1273 Å^3 (cubic ångströms) | 727.7 Å^3 (cubic ångströms) d-spacing | 8.977 Å (ångströms) | 7.791 Å (ångströms) | 4.696 Å (ångströms) | 5.06 Å (ångströms) | 3.06 Å (ångströms) | 3.12 Å (ångströms) intensity | 100% | 87% | 48% | 100% | 80% | 70% molecules per unit cell | 4 molecules per cell | 3 molecules per cell 2V angle | 22 π/45 radians≈88° (degrees) | refractive indices | 1.459 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1.75 | 0 dispersion | none | unit cell lengths | 7.44 Å (ångströms) | 15.58 Å (ångströms) | 11.7 Å (ångströms) | 7.18 Å (ångströms) | 16.3 Å (ångströms) | 16.3 Å (ångströms) unit cell angles | 90° (degrees) | 110.2° (degrees) | 90° (degrees) | 90° (degrees) | 90° (degrees) | 120° (degrees)

Aluminite is a hydrous aluminium sulfate mineral with formula: Al_2SO_4(OH)_4·7H_2O. It is an earthy white to gray-white monoclinic mineral which almost never exhibits crystal form. It forms botryoidal to mammillary clay-like masses. It has a very soft Mohs hardness of 1-2 and a specific gravity of 1.66-1.82.