Herderite
CaBe(PO4)FIMA symbol: Hrdgrandfathered
Herderite is a phosphate, arsenate, or vanadate mineral with the formula CaBe(PO4)F, crystallizing in the monoclinic system. It has a Mohs hardness of 5, typically white, green or yellow in color, with a resinous or vitreous luster, a specific gravity of 2.99-3.01.
Photos
Crystallography
| Crystal system | monoclinic crystal systemWikidata (CC0) |
|---|---|
| Space group | P 1 21/a 1 |
| Cell (Å, °) | a = 9.7446, b = 7.6769, c = 4.7633; α = 90, β = 90.667, γ = 90 |
| Cell volume | 356.31 ų, Z = 4 |
| Axial ratios | 1.2693:1:0.6205calculated from COD 9013172 |
| Source structure | COD 9013172 (American Mineralogist, 2008) — 1 of 4 structures |
Powder X-ray diffraction (calculated)
| d (Å) | 3.128 | 3.098 | 2.989 | 3.386 | 2.863 | 2.851 |
|---|---|---|---|---|---|---|
| I/I₀ | 100 | 81.6 | 60 | 49.6 | 46.8 | 43.1 |
xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 9013172; idealized occupancies, no preferred orientation.
Physical properties
| Density (calculated) | 3.027 g/cm³calculated from COD 9013172 |
|---|---|
| Hardness (Mohs) | 5single sourceDana, System of Mineralogy, 6th ed. (1892) |
| Specific gravity | 2.99-3.01 g/cm3corroboratedDana, System of Mineralogy, 6th ed. (1892) |
| Color | green, white, yellowsingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Luster | resinous, vitreoussingle sourceDana, System of Mineralogy, 6th ed. (1892) |
Chemistry (calculated)
| Molecular weight | 163.06 g/molcalculated from the IMA formula |
|---|---|
| Composition (wt%) | Ca 24.58%, Be 5.53%, P 19%, O 39.25%, F 11.65% |
Classification
| Nickel-Strunz (10th) | 8.BA.10Wikidata (CC0) |
|---|---|
| Nickel-Strunz (9th) | 8.BA.10Wikidata (CC0) |
| Dana (8th) | 41.5.4.1Wikidata (CC0) |