Mineral Factbook

Aluminite

Al2(SO4)(OH)4·7H2OIMA symbol: Agrandfathered

Aluminite is a sulfate mineral with the formula Al2(SO4)(OH)4·7H2O, crystallizing in the monoclinic system. It has a Mohs hardness of 1-2, typically white in color, with a dull or earthy luster, a specific gravity of 1.66. Its streak is white.

Photos

Aluminite specimen photo
Caruso 308 · CC BY-SA 4.0 · Commons
Aluminite specimen photo
Mai Seppel · CC BY-SA 4.0 · Commons
Aluminite specimen photo
Mai Seppel · CC BY-SA 4.0 · Commons
Aluminite specimen photo
Ra'ike (see also: de:Benutzer:Ra'ike) · CC BY-SA 3.0 · Commons

Crystallography

Crystal systemmonoclinic crystal systemWikidata (CC0)
Space groupP 1 21/c 1
Cell (Å, °)a = 7.44, b = 15.583, c = 11.7; α = 90, β = 110.18, γ = 90
Cell volume1273.2 ų, Z = 4
Axial ratios0.4774:1:0.7508calculated from COD 9007626
Source structureCOD 9007626 (Acta Crystallographica, Section B, 1978)

Powder X-ray diffraction (calculated)

2θ (degrees, Cu Kα1)I/I₀ (max 100)
d (Å)7.7918.9774.6963.7355.0135.491
I/I₀10087.774.758.450.143.7

xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 9007626; idealized occupancies, no preferred orientation.

Physical properties

Density (calculated)1.795 g/cm³calculated from COD 9007626
Hardness (Mohs)
1-2single sourceDana, System of Mineralogy, 6th ed. (1892)
Specific gravity
1.66 g/cm3single sourceDana, System of Mineralogy, 6th ed. (1892)
Color
whitesingle sourceDana, System of Mineralogy, 6th ed. (1892)
Streak
whitesingle sourceWikidata (CC0)
Luster
dull, earthysingle sourceDana, System of Mineralogy, 6th ed. (1892)

Chemistry (calculated)

Molecular weight344.16 g/molcalculated from the IMA formula
Composition (wt%)Al 15.68%, S 9.32%, O 69.73%, H 5.27%

Classification

Nickel-Strunz (10th)7.DC.05Wikidata (CC0)
Nickel-Strunz (9th)7.DC.05Wikidata (CC0)