Mineral Factbook

Spinel

MgAl2O4IMA symbol: Splgrandfathered

Spinel is an oxide or hydroxide mineral with the formula MgAl2O4, crystallizing in the cubic system. It has a Mohs hardness of 3-3.25, typically gray in color, with a dull or pearly luster, a specific gravity of 2.633. Its streak is white.

Photos

Spinel specimen photo
Osama Shukir Muhammed Amin FRCP(Glasg) · CC BY-SA 4.0 · Commons
Spinel specimen photo
Ma, C.; Cámara, F.; Bindi, L.; Griffin, W.L. · CC BY 4.0 · Commons
Spinel specimen photo
Mai Seppel · CC BY-SA 4.0 · Commons
Spinel specimen photo
Mai Seppel · CC BY-SA 4.0 · Commons

Crystallography

Crystal systemcubic crystal systemWikidata (CC0)
Space groupF d -3 m :2
Cell (Å, °)a = 8.1334, b = 8.1334, c = 8.1334; α = 90, β = 90, γ = 90
Cell volume538.042 ų, Z = 8
Axial ratios1.0000:1:1.0000calculated from COD 9017029
Source structureCOD 9017029 (American Mineralogist, 2014) — 1 of 646 structures

Powder X-ray diffraction (calculated)

2θ (degrees, Cu Kα1)I/I₀ (max 100)
d (Å)2.4521.4381.5652.0332.8764.696
I/I₀10066.145.838.837.917.5

xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 9017029; idealized occupancies, no preferred orientation.

Physical properties

Density (calculated)3.85 g/cm³calculated from COD 9017029
Hardness (Mohs)
8single sourceWikidata (CC0)
3-3.25single sourceDana's System, 2nd Appendix (1909)
Specific gravity
2.633 g/cm3single sourceDana's System, 2nd Appendix (1909)
Color
graysingle sourceDana's System, 2nd Appendix (1909)
Streak
whitesingle sourceWikidata (CC0)
Luster
dull, pearlysingle sourceDana's System, 2nd Appendix (1909)

Chemistry (calculated)

Molecular weight142.27 g/molcalculated from the IMA formula
Composition (wt%)Mg 17.08%, Al 37.93%, O 44.98%

Classification

Nickel-Strunz (10th)4.BB.05Wikidata (CC0)
Nickel-Strunz (9th)4.BB.05Wikidata (CC0)
Dana (8th)7.2.1.1Wikidata (CC0)