Mineral Factbook

Chromite

Fe2+Cr2O4IMA symbol: Chrgrandfathered

Chromite is an oxide or hydroxide mineral with the formula Fe2+Cr2O4, crystallizing in the cubic system. It has a Mohs hardness of 5.5, a specific gravity of 4.239. Its streak is brown.

Photos

Chromite specimen photo
Matina Tsou · CC BY-SA 4.0 · Commons
Chromite specimen photo
James St. John · CC BY 2.0 · Commons
Chromite specimen photo
Reinhard Kraasch · CC BY-SA 4.0 · Commons
Chromite specimen photo
James St. John · CC BY 2.0 · Commons

Crystallography

Crystal systemcubic crystal systemWikidata (CC0)
Space groupF d -3 m :2
Cell (Å, °)a = 8.3264, b = 8.3264, c = 8.3264; α = 90, β = 90, γ = 90
Cell volume577.26 ų, Z = 8
Axial ratios1.0000:1:1.0000calculated from COD 9013665
Source structureCOD 9013665 (American Mineralogists, 2009) — 1 of 38 structures

Powder X-ray diffraction (calculated)

2θ (degrees, Cu Kα1)I/I₀ (max 100)
d (Å)2.5111.4721.6022.0824.8072.944
I/I₀10052.138.137.334.521.6

xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 9013665; idealized occupancies, no preferred orientation.

Physical properties

Density (calculated)4.59 g/cm³calculated from COD 9013665
Hardness (Mohs)
5.5single sourceWikidata (CC0)
Specific gravity
4.239 g/cm3single sourceDana's System, 2nd Appendix (1909)
Streak
brownsingle sourceWikidata (CC0)

Classification

Nickel-Strunz (10th)4.BB.05Wikidata (CC0)
Nickel-Strunz (9th)4.BB.05Wikidata (CC0)
Dana (8th)7.2.3.3Wikidata (CC0)