Mineral Factbook

Skutterudite

CoAs3IMA symbol: Sktgrandfathered

Skutterudite is a sulfide or sulfosalt mineral with the formula CoAs3, crystallizing in the cubic system. It has a Mohs hardness of 6, typically white or gray in color, with a metallic luster, a specific gravity of 6.72-6.86. Its streak is black.

Photos

Skutterudite specimen photo
Jan Helebrant · CC BY-SA 2.0 · Commons
Skutterudite specimen photo
Jan Helebrant · CC BY-SA 2.0 · Commons
Skutterudite specimen photo
Ra'ike (see also: de:Benutzer:Ra'ike) · CC BY-SA 3.0 · Commons
Skutterudite specimen photo
Robert M. Lavinsky · CC BY-SA 3.0 · Commons

Crystallography

Crystal systemcubic crystal systemWikidata (CC0)
Space groupI m -3
Cell (Å, °)a = 8.2055, b = 8.2055, c = 8.2055; α = 90, β = 90, γ = 90
Cell volume552.478 ų, Z = 8
Axial ratios1.0000:1:1.0000calculated from COD 9016286
Source structureCOD 9016286 (Acta Chemica Scandinavica A, 1974) — 1 of 5 structures

Powder X-ray diffraction (calculated)

2θ (degrees, Cu Kα1)I/I₀ (max 100)
d (Å)2.5951.8351.6092.1931.6751.21
I/I₀10035.330.728.720.314

xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 9016286; idealized occupancies, no preferred orientation.

Physical properties

Density (calculated)6.822 g/cm³calculated from COD 9016286
Hardness (Mohs)
6single sourceDana, System of Mineralogy, 6th ed. (1892)
Specific gravity
6.72-6.86 g/cm3corroboratedDana, System of Mineralogy, 6th ed. (1892)
Color
gray, whitesingle sourceDana, System of Mineralogy, 6th ed. (1892)
Streak
blacksingle sourceWikidata (CC0)
Luster
metallicsingle sourceDana, System of Mineralogy, 6th ed. (1892)

Chemistry (calculated)

Molecular weight283.7 g/molcalculated from the IMA formula
Composition (wt%)Co 20.77%, As 79.23%

Classification

Nickel-Strunz (10th)2.EC.05Wikidata (CC0)
Nickel-Strunz (9th)2.EC.05Wikidata (CC0)