Ilmenite
Fe2+Ti4+O3IMA symbol: Ilmgrandfathered
Ilmenite is an oxide or hydroxide mineral with the formula Fe2+Ti4+O3, crystallizing in the trigonal system. It has a Mohs hardness of 5-6, typically black in color, with a metallic or submetallic luster, a specific gravity of 4.5-5. Its streak is black or brown.
Photos
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Crystallography
| Crystal system | trigonal crystal systemWikidata (CC0) |
|---|---|
| Space group | R -3 |
| Cell (Å, °) | a = 5.08854, b = 5.08854, c = 14.0924; α = 90, β = 90, γ = 120 |
| Cell volume | 316.011 ų, Z = 6 |
| Axial ratios | 1.0000:1:2.7694calculated from COD 1544716 |
| Source structure | COD 1544716 (Mineralogical Journal, 1989) — 1 of 56 structures |
Powder X-ray diffraction (calculated)
| d (Å) | 2.752 | 2.544 | 1.726 | 1.868 | 1.469 | 1.506 |
|---|---|---|---|---|---|---|
| I/I₀ | 100 | 70 | 52.2 | 38.3 | 32.6 | 32.3 |
xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 1544716; idealized occupancies, no preferred orientation.
Physical properties
| Density (calculated) | 4.776 g/cm³calculated from COD 1544716 |
|---|---|
| Hardness (Mohs) | 5.5single sourceWikidata (CC0) 5-6single sourceDana, System of Mineralogy, 6th ed. (1892) |
| Specific gravity | 4.5-5 g/cm3corroboratedDana, System of Mineralogy, 6th ed. (1892) |
| Color | blacksingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Streak | blacksingle sourceWikidata (CC0) black, brown, redsingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Luster | metallic, submetallicsingle sourceDana, System of Mineralogy, 6th ed. (1892) |
Classification
| Nickel-Strunz (10th) | 4.CB.05Wikidata (CC0) |
|---|---|
| Nickel-Strunz (9th) | 4.CB.05Wikidata (CC0) |
| Dana (8th) | 4.3.5.1Wikidata (CC0) |