Diaspore
AlO(OH)IMA symbol: Dspgrandfathered
Diaspore is an oxide or hydroxide mineral with the formula AlO(OH). It has a Mohs hardness of 6.5-7, typically colorless, white, blue or brown in color, with a pearly or vitreous luster, a specific gravity of 3.3-3.5. Cleavage is eminent.
Photos
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Crystallography
| Space group | P b n m |
|---|---|
| Cell (Å, °) | a = 4.4031, b = 9.4252, c = 2.8452; α = 90, β = 90, γ = 90 |
| Cell volume | 118.1 ų, Z = 4 |
| Axial ratios | 0.4672:1:0.3019calculated from COD 1008769 |
| Source structure | COD 1008769 (Materials Science Forum, 1991) — 1 of 18 structures |
Powder X-ray diffraction (calculated)
| d (Å) | 3.989 | 2.316 | 1.633 | 2.078 | 2.131 | 1.48 |
|---|---|---|---|---|---|---|
| I/I₀ | 100 | 50.5 | 44.4 | 38.6 | 38.3 | 21.2 |
xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 1008769; idealized occupancies, no preferred orientation.
Physical properties
| Density (calculated) | 3.346 g/cm³calculated from COD 1008769 |
|---|---|
| Hardness (Mohs) | 6.5-7single sourceDana, System of Mineralogy, 6th ed. (1892) |
| Specific gravity | 3.3-3.5 g/cm3corroboratedDana, System of Mineralogy, 6th ed. (1892) |
| Color | blue, brown, colorless, gray, green, red, violet, white, yellowsingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Luster | pearly, vitreoussingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Cleavage | eminentDana, System of Mineralogy, 6th ed. (1892) |
Chemistry (calculated)
| Molecular weight | 59.99 g/molcalculated from the IMA formula |
|---|---|
| Composition (wt%) | Al 44.98%, O 53.34%, H 1.68% |
Classification
| Nickel-Strunz (10th) | 4.FD.10Wikidata (CC0) |
|---|---|
| Nickel-Strunz (9th) | 4.FD.10Wikidata (CC0) |
| Dana (8th) | 6.1.1.1Wikidata (CC0) |