Matlockite
PbClFIMA symbol: Mtlgrandfathered
Matlockite is a halide mineral with the formula PbClF, crystallizing in the tetragonal system. It has a Mohs hardness of 2.5-3, typically green or yellow in color, with an adamantine or pearly luster, a specific gravity of 7.21. Cleavage is imperfect.
Photos
Crystallography
| Crystal system | tetragonal crystal systemWikidata (CC0) |
|---|---|
| Space group | P 4/n m m :2 |
| Cell (Å, °) | a = 4.11, b = 4.11, c = 7.246; α = 90, β = 90, γ = 90 |
| Cell volume | 122.4 ų, Z = 2 |
| Axial ratios | 1.0000:1:1.7630calculated from COD 9011802 |
| Source structure | COD 9011802 (Mineralogical Magazine, 1996) — 1 of 4 structures |
Powder X-ray diffraction (calculated)
| d (Å) | 3.575 | 2.906 | 2.267 | 2.718 | 1.782 | 2.055 |
|---|---|---|---|---|---|---|
| I/I₀ | 100 | 52.7 | 45.6 | 36.6 | 31.3 | 27.2 |
xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 9011802; idealized occupancies, no preferred orientation.
Physical properties
| Density (calculated) | 7.099 g/cm³calculated from COD 9011802 |
|---|---|
| Hardness (Mohs) | 2.5-3single sourceDana, System of Mineralogy, 6th ed. (1892) |
| Specific gravity | 7.21 g/cm3corroboratedDana, System of Mineralogy, 6th ed. (1892) |
| Color | green, yellowsingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Luster | adamantine, pearlysingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Cleavage | imperfectDana, System of Mineralogy, 6th ed. (1892) |
Chemistry (calculated)
| Molecular weight | 261.65 g/molcalculated from the IMA formula |
|---|---|
| Composition (wt%) | Pb 79.19%, Cl 13.55%, F 7.26% |
Classification
| Nickel-Strunz (10th) | 3.DC.25Wikidata (CC0) |
|---|---|
| Nickel-Strunz (9th) | 3.DC.25Wikidata (CC0) |