Mineral Factbook

Alum-(K)

KAl(SO4)2·12H2OIMA symbol: Aum-Krenamed

Alum-(K) is a sulfate mineral with the formula KAl(SO4)2·12H2O, crystallizing in the cubic system. It has a calculated density of 1.751 g/cm3.

Photos

Alum-(K) specimen photo
Koreller · CC BY-SA 4.0 · Commons
Alum-(K) specimen photo
Koreller · CC BY-SA 4.0 · Commons
Alum-(K) specimen photo
Mai Seppel · CC BY-SA 4.0 · Commons
Alum-(K) specimen photo
Udine2812 · CC BY-SA 4.0 · Commons

Crystallography

Crystal systemcubic crystal systemWikidata (CC0)
Space groupP a -3
Cell (Å, °)a = 12.164, b = 12.164, c = 12.164; α = 90, β = 90, γ = 90
Cell volume1799.82 ų, Z = 4
Axial ratios1.0000:1:1.0000calculated from COD 2102035
Source structureCOD 2102035 (Acta Crystallographica Section B, 2000) — 1 of 4 structures

Powder X-ray diffraction (calculated)

2θ (degrees, Cu Kα1)I/I₀ (max 100)
d (Å)4.3013.2514.0552.7915.443.041
I/I₀10059.448.138.332.425.9

xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 2102035; idealized occupancies, no preferred orientation.

Physical properties

Density (calculated)1.751 g/cm³calculated from COD 2102035

Chemistry (calculated)

Molecular weight474.39 g/molcalculated from the IMA formula
Composition (wt%)K 8.24%, Al 5.69%, S 13.52%, O 67.45%, H 5.1%

Classification

Nickel-Strunz (10th)7.CC.20Wikidata (CC0)
Nickel-Strunz (9th)7.CC.20Wikidata (CC0)
Dana (8th)29.5.5.1Wikidata (CC0)