Scolecite
Ca(Si3Al2)O10·3H2OIMA symbol: Slcapproved
Scolecite is a silicate mineral with the formula Ca(Si3Al2)O10·3H2O, crystallizing in the monoclinic system. It has a Mohs hardness of 5-5.5, with a silky or vitreous luster, a specific gravity of 2.16-2.4. Its streak is white; cleavage is perfect.
Photos
Crystallography
| Crystal system | monoclinic crystal systemWikidata (CC0) |
|---|---|
| Space group | F 1 d 1 |
| Cell (Å, °) | a = 18.489, b = 18.959, c = 6.519; α = 90, β = 90.611, γ = 90 |
| Cell volume | 2284.99 ų, Z = 8 |
| Axial ratios | 0.9752:1:0.3438calculated from COD 9007696 |
| Source structure | COD 9007696 (Acta Crystallographica, Section B, 1998) — 1 of 7 structures |
Powder X-ray diffraction (calculated)
| d (Å) | 5.866 | 2.887 | 2.856 | 6.618 | 4.38 | 2.933 |
|---|---|---|---|---|---|---|
| I/I₀ | 100 | 67.1 | 56.8 | 53.6 | 44 | 41.3 |
xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 9007696; idealized occupancies, no preferred orientation.
Physical properties
| Density (calculated) | 2.281 g/cm³calculated from COD 9007696 |
|---|---|
| Hardness (Mohs) | 5-5.5single sourceDana, System of Mineralogy, 6th ed. (1892) |
| Specific gravity | 2.16-2.4 g/cm3corroboratedDana, System of Mineralogy, 6th ed. (1892) |
| Streak | whitesingle sourceWikidata (CC0) |
| Luster | silky, vitreoussingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Cleavage | perfectDana, System of Mineralogy, 6th ed. (1892) |
Chemistry (calculated)
| Molecular weight | 392.34 g/molcalculated from the IMA formula |
|---|---|
| Composition (wt%) | Ca 10.22%, Si 21.48%, Al 13.75%, O 53.01%, H 1.54% |
Classification
| Nickel-Strunz (10th) | 9.GA.05Wikidata (CC0) |
|---|---|
| Nickel-Strunz (9th) | 9.GA.05Wikidata (CC0) |