Montroydite
HgOIMA symbol: Mtydgrandfathered
Montroydite is an oxide or hydroxide mineral with the formula HgO. It has a Mohs hardness of 1.5-2, typically orange or red in color, with an adamantine or vitreous luster, a calculated density of 11.189 g/cm3. Its streak is orange or red.
Photos




Crystallography
| Space group | P n m a |
|---|---|
| Cell (Å, °) | a = 6.6129, b = 5.5208, c = 3.5219; α = 90, β = 90, γ = 90 |
| Cell volume | 128.579 ų, Z = 4 |
| Axial ratios | 1.1978:1:0.6379calculated from COD 9012530 |
| Source structure | COD 9012530 (Acta Chemica Scandinavica, 1964) |
Powder X-ray diffraction (calculated)
| d (Å) | 2.969 | 2.837 | 2.411 | 1.816 | 2.76 | 1.496 |
|---|---|---|---|---|---|---|
| I/I₀ | 100 | 80.6 | 67.8 | 58 | 53.9 | 30 |
xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 9012530; idealized occupancies, no preferred orientation.
Physical properties
| Density (calculated) | 11.189 g/cm³calculated from COD 9012530 |
|---|---|
| Hardness (Mohs) | 1.5-2Dana's System, 2nd Appendix (1909) |
| Color | orange, redDana's System, 2nd Appendix (1909) |
| Streak | orange, redDana's System, 2nd Appendix (1909) |
| Luster | adamantine, vitreousDana's System, 2nd Appendix (1909) |
Chemistry (calculated)
| Molecular weight | 216.59 g/molcalculated from the IMA formula |
|---|---|
| Composition (wt%) | Hg 92.61%, O 7.39% |
Classification
| Nickel-Strunz (10th) | 4.AC.15Wikidata (CC0) |
|---|---|
| Nickel-Strunz (9th) | 4.AC.15Wikidata (CC0) |
| Dana (8th) | 4.2.6.1Wikidata (CC0) |