Augite
(Ca,Mg,Fe)2Si2O6IMA symbol: Augapproved
Augite is a silicate mineral with the formula (Ca,Mg,Fe)2Si2O6, crystallizing in the monoclinic system. It has a Mohs hardness of 6, typically blue or violet in color, with a silky luster, a specific gravity of 3.233.
Photos
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Crystallography
| Crystal system | monoclinic crystal systemWikidata (CC0) |
|---|---|
| Space group | C 1 2/c 1 |
| Cell (Å, °) | a = 9.7504, b = 8.9015, c = 5.27444; α = 90, β = 106.016, γ = 90 |
| Cell volume | 440.016 ų, Z = 4 |
| Axial ratios | 1.0954:1:0.5925calculated from COD 9009664 |
| Source structure | COD 9009664 (Journal of Applied Crystallography, 2000) — 1 of 4 structures |
Powder X-ray diffraction (calculated)
| d (Å) | 2.992 | 2.948 | 2.515 | 2.535 | 2.563 | 3.227 |
|---|---|---|---|---|---|---|
| I/I₀ | 100 | 40.2 | 38.9 | 38.6 | 36 | 34.1 |
xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 9009664; idealized occupancies, no preferred orientation.
Physical properties
| Density (calculated) | 3.384 g/cm³calculated from COD 9009664 |
|---|---|
| Hardness (Mohs) | 6single sourceDana, System of Mineralogy, 6th ed. (1892) |
| Specific gravity | 3.233 g/cm3corroboratedDana, System of Mineralogy, 6th ed. (1892) |
| Color | blue, violetsingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Luster | silkysingle sourceDana, System of Mineralogy, 6th ed. (1892) |
Classification
| Nickel-Strunz (10th) | 9.DA.15Wikidata (CC0) |
|---|---|
| Nickel-Strunz (9th) | 9.DA.15Wikidata (CC0) |
| Dana (8th) | 65.1.3a.3Wikidata (CC0) |