Beryl
Be3Al2Si6O18IMA symbol: Brlgrandfathered
Beryl is a silicate mineral with the formula Be3Al2Si6O18, crystallizing in the hexagonal system. It has a Mohs hardness of 7.5-8, typically white, blue, green or red in color, with a vitreous luster, a specific gravity of 2.63-2.8. Its streak is white.
Photos
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Crystallography
| Crystal system | hexagonal crystal systemWikidata (CC0) |
|---|---|
| Space group | P 6/m c c |
| Cell (Å, °) | a = 9.258, b = 9.258, c = 9.156; α = 90, β = 90, γ = 120 |
| Cell volume | 679.627 ų, Z = 2 |
| Axial ratios | 1.0000:1:0.9890calculated from COD 9014734 |
| Source structure | COD 9014734 (The Canadian Mineralogist, 2010) — 1 of 47 structures |
Powder X-ray diffraction (calculated)
| d (Å) | 3.255 | 2.877 | 8.018 | 4.578 | 3.016 | 3.976 |
|---|---|---|---|---|---|---|
| I/I₀ | 100 | 81.3 | 32.9 | 20 | 19.6 | 17.2 |
xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 9014734; idealized occupancies, no preferred orientation.
Physical properties
| Density (calculated) | 2.851 g/cm³calculated from COD 9014734 |
|---|---|
| Hardness (Mohs) | 7.5-8single sourceDana, System of Mineralogy, 6th ed. (1892) |
| Specific gravity | 2.63-2.8 g/cm3single sourceDana, System of Mineralogy, 6th ed. (1892) |
| Color | blue, green, red, rose, white, yellowsingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Streak | whitesingle sourceWikidata (CC0) whitesingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Luster | vitreoussingle sourceDana, System of Mineralogy, 6th ed. (1892) |
Chemistry (calculated)
| Molecular weight | 537.5 g/molcalculated from the IMA formula |
|---|---|
| Composition (wt%) | Be 5.03%, Al 10.04%, Si 31.35%, O 53.58% |
Classification
| Nickel-Strunz (10th) | 9.CJ.05Wikidata (CC0) |
|---|---|
| Nickel-Strunz (9th) | 9.CJ.05Wikidata (CC0) |
| Dana (8th) | 61.1.1.1Wikidata (CC0) |