Yttrialite-(Y)
Y2Si2O7IMA symbol: Ytt-Yrenamed
Yttrialite-(Y) is a silicate mineral with the formula Y2Si2O7, crystallizing in the monoclinic system. It has a Mohs hardness of 5-5.5, typically green, orange or yellow in color, with a greasy or vitreous luster, a specific gravity of 4.575. Cleavage is none.
Photos
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Crystallography
| Crystal system | monoclinic crystal systemWikidata (CC0) |
|---|---|
| Space group | P 1 21/m 1 |
| Cell (Å, °) | a = 7.5, b = 8.06, c = 5.02; α = 90, β = 112, γ = 90 |
| Cell volume | 281.362 ų, Z = 2 |
| Axial ratios | 0.9305:1:0.6228calculated from COD 9009430 |
| Source structure | COD 9009430 (Kristallografiya, 1971) |
Powder X-ray diffraction (calculated)
| d (Å) | 3.047 | 2.633 | 4.654 | 2.389 | 2.634 | 3.48 |
|---|---|---|---|---|---|---|
| I/I₀ | 100 | 31.1 | 26.2 | 24.7 | 21.8 | 20.1 |
xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 9009430; idealized occupancies, no preferred orientation.
Physical properties
| Density (calculated) | 4.084 g/cm³calculated from COD 9009430 |
|---|---|
| Hardness (Mohs) | 5-5.5single sourceDana, System of Mineralogy, 6th ed. (1892) |
| Specific gravity | 4.575 g/cm3single sourceDana, System of Mineralogy, 6th ed. (1892) |
| Color | green, orange, yellowsingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Luster | greasy, vitreoussingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Cleavage | noneDana, System of Mineralogy, 6th ed. (1892) |
Chemistry (calculated)
| Molecular weight | 345.98 g/molcalculated from the IMA formula |
|---|---|
| Composition (wt%) | Y 51.39%, Si 16.24%, O 32.37% |
Classification
| Nickel-Strunz (10th) | 9.BC.05Wikidata (CC0) |
|---|---|
| Nickel-Strunz (9th) | 9.BC.05Wikidata (CC0) |
| Dana (8th) | 55.2.1b.3Wikidata (CC0) |