Monticellite
CaMg(SiO4)IMA symbol: Mtcgrandfathered
Monticellite is a silicate mineral with the formula CaMg(SiO4), crystallizing in the orthorhombic system. It has a Mohs hardness of 5-5.5, typically gray, green or yellow in color, with a resinous or vitreous luster, a specific gravity of 3.033. Its streak is red.
Photos
Crystallography
| Crystal system | orthorhombic crystal systemWikidata (CC0) |
|---|---|
| Space group | P n m a |
| Cell (Å, °) | a = 11.1098, b = 6.3894, c = 4.8281; α = 90, β = 90, γ = 90 |
| Cell volume | 342.722 ų, Z = 4 |
| Axial ratios | 1.7388:1:0.7556calculated from COD 9016495 |
| Source structure | COD 9016495 (Acta Crystallographica, Section B, 1995) — 1 of 15 structures |
Powder X-ray diffraction (calculated)
| d (Å) | 2.67 | 2.591 | 1.82 | 2.938 | 3.639 | 1.602 |
|---|---|---|---|---|---|---|
| I/I₀ | 100 | 76.8 | 61.7 | 50 | 49.1 | 35.2 |
xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 9016495; idealized occupancies, no preferred orientation.
Physical properties
| Density (calculated) | 3.106 g/cm³calculated from COD 9016495 |
|---|---|
| Hardness (Mohs) | 5-5.5single sourceDana, System of Mineralogy, 6th ed. (1892) |
| Specific gravity | 3.033 g/cm3corroboratedDana, System of Mineralogy, 6th ed. (1892) |
| Color | gray, green, yellowsingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Streak | redsingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Luster | resinous, vitreoussingle sourceDana, System of Mineralogy, 6th ed. (1892) |
Chemistry (calculated)
| Molecular weight | 156.47 g/molcalculated from the IMA formula |
|---|---|
| Composition (wt%) | Ca 25.61%, Mg 15.53%, Si 17.95%, O 40.9% |
Classification
| Nickel-Strunz (10th) | 9.AC.10Wikidata (CC0) |
|---|---|
| Nickel-Strunz (9th) | 9.AC.10Wikidata (CC0) |
| Dana (8th) | 51.3.2.1Wikidata (CC0) |