Mineral Factbook

Bustamite

Mn2Ca2MnCa(Si3O9)2IMA symbol: Bstgrandfathered

Bustamite is a silicate mineral with the formula Mn2Ca2MnCa(Si3O9)2, crystallizing in the triclinic system. It has a calculated density of 3.484 g/cm3. Its streak is white.

Photos

Bustamite specimen photo
Lodewicus de Honsvels · CC BY-SA 4.0 · Commons
Bustamite specimen photo
Stephen E. Fritz · CC BY 3.0 · Commons
Bustamite specimen photo
Dave Dyet http://www.shutterstone.com http://www.dyet.com · Public domain · Commons
Bustamite specimen photo
Leon Hupperichs · CC BY-SA 3.0 · Commons

Crystallography

Crystal systemtriclinic crystal systemWikidata (CC0)
Space groupI -1
Cell (Å, °)a = 9.807, b = 10.68, c = 7.091; α = 99.58, β = 99.99, γ = 83.79
Cell volume718.832 ų, Z = 12
Axial ratios0.9183:1:0.6640calculated from COD 9000606
Source structureCOD 9000606 (American Mineralogist, 1978) — 1 of 4 structures

Powder X-ray diffraction (calculated)

2θ (degrees, Cu Kα1)I/I₀ (max 100)
d (Å)2.8862.8723.2053.0011.7733.411
I/I₀10090.648.347.33734.2

xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 9000606; idealized occupancies, no preferred orientation.

Physical properties

Density (calculated)3.484 g/cm³calculated from COD 9000606
Streak
whitesingle sourceWikidata (CC0)

Chemistry (calculated)

Molecular weight741.55 g/molcalculated from the IMA formula
Composition (wt%)Mn 22.23%, Ca 16.21%, Si 22.72%, O 38.84%

Classification

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