Friedelite
Mn2+8Si6O15(OH)10IMA symbol: Fdlgrandfathered
Friedelite is a silicate mineral with the formula Mn2+8Si6O15(OH)10, crystallizing in the monoclinic system. It has a Mohs hardness of 4-5, typically red or rose in color, a specific gravity of 3.07. Its streak is rose; cleavage is perfect.
Photos
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Crystallography
| Crystal system | monoclinic crystal systemWikidata (CC0) |
|---|---|
| Space group | C 1 2/m 1 |
| Cell (Å, °) | a = 23.28, b = 13.44, c = 7.428; α = 90, β = 104.98, γ = 90 |
| Cell volume | 2245.11 ų, Z = 4 |
| Axial ratios | 1.7321:1:0.5527calculated from COD 9012817 |
| Source structure | COD 9012817 (Yamaguchi University, College of Arts Bulletin, 1992) |
Physical properties
| Density (calculated) | 3.04 g/cm³calculated from COD 9012817 |
|---|---|
| Hardness (Mohs) | 4-5single sourceDana, System of Mineralogy, 6th ed. (1892) |
| Specific gravity | 3.07 g/cm3corroboratedDana, System of Mineralogy, 6th ed. (1892) |
| Color | red, rosesingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Streak | roseDana, System of Mineralogy, 6th ed. (1892) |
| Cleavage | perfectDana, System of Mineralogy, 6th ed. (1892) |
Classification
| Nickel-Strunz (10th) | 9.EE.10Wikidata (CC0) |
|---|---|
| Nickel-Strunz (9th) | 9.EE.10Wikidata (CC0) |