Mineral Factbook

Sapphirine

Mg4(Mg3Al9)O4[Si3Al9O36]IMA symbol: Sprgrandfathered

Sapphirine is a silicate mineral with the formula Mg4(Mg3Al9)O4[Si3Al9O36], crystallizing in the monoclinic system. It has a Mohs hardness of 7.5, typically blue or green in color, with a vitreous luster, a specific gravity of 3.42-3.48. Its streak is white.

Photos

Sapphirine specimen photo
Ma, C.; Cámara, F.; Bindi, L.; Toledo, V.; Griffin, W.L. · CC BY 4.0 · Commons
Sapphirine specimen photo
Parent Géry · CC BY-SA 3.0 · Commons
Sapphirine specimen photo
Parent Géry · CC BY-SA 3.0 · Commons
Sapphirine specimen photo
Shakko · CC BY-SA 4.0 · Commons

Crystallography

Crystal systemmonoclinic crystal systemWikidata (CC0)
Space groupP -1
Cell (Å, °)a = 8.822, b = 9.794, c = 10.256; α = 63.82, β = 84.77, γ = 65.32
Cell volume717.875 ų, Z = 4
Axial ratios0.9008:1:1.0472calculated from COD 9005376
Source structureCOD 9005376 (European Journal of Mineralogy, 1998) — 1 of 5 structures

Powder X-ray diffraction (calculated)

2θ (degrees, Cu Kα1)I/I₀ (max 100)
d (Å)2.5272.5232.5223.083.081.481
I/I₀10096.895.673.27262.7

xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 9005376; idealized occupancies, no preferred orientation.

Physical properties

Density (calculated)5.097 g/cm³calculated from COD 9005376
Hardness (Mohs)
7.5single sourceDana, System of Mineralogy, 6th ed. (1892)
Specific gravity
3.42-3.48 g/cm3single sourceDana, System of Mineralogy, 6th ed. (1892)
Color
blue, greensingle sourceDana, System of Mineralogy, 6th ed. (1892)
Streak
whitesingle sourceWikidata (CC0)
Luster
vitreoussingle sourceDana, System of Mineralogy, 6th ed. (1892)

Chemistry (calculated)

Molecular weight1380.04 g/molcalculated from the IMA formula
Composition (wt%)Mg 12.33%, Al 35.19%, O 46.37%, Si 6.11%

Classification

Nickel-Strunz (10th)9.DH.45Wikidata (CC0)
Nickel-Strunz (9th)9.DH.45Wikidata (CC0)