Wardite
NaAl3(PO4)2(OH)4·2H2OIMA symbol: Wdgrandfathered
Wardite is a phosphate, arsenate, or vanadate mineral with the formula NaAl3(PO4)2(OH)4·2H2O, crystallizing in the tetragonal system. It has a Mohs hardness of 5, typically gray in color, a specific gravity of 2.7.
Photos



Crystallography
| Crystal system | tetragonal crystal systemWikidata (CC0) |
|---|---|
| Space group | P 41 21 2 |
| Cell (Å, °) | a = 7.03, b = 7.03, c = 19.04; α = 90, β = 90, γ = 90 |
| Cell volume | 940.974 ų, Z = 4 |
| Axial ratios | 1.0000:1:2.7084calculated from COD 9009442 |
| Source structure | COD 9009442 (Mineralogical Magazine, 1970) |
Powder X-ray diffraction (calculated)
| d (Å) | 4.711 | 2.985 | 3.075 | 2.583 | 3.102 | 1.511 |
|---|---|---|---|---|---|---|
| I/I₀ | 100 | 74.6 | 68.5 | 64 | 44.3 | 40.9 |
xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 9009442; idealized occupancies, no preferred orientation.
Physical properties
| Density (calculated) | 2.752 g/cm³calculated from COD 9009442 |
|---|---|
| Hardness (Mohs) | 5single sourceFord, Dana's Textbook of Mineralogy, 3rd ed. (1922) |
| Specific gravity | 2.7 g/cm3corroboratedFord, Dana's Textbook of Mineralogy, 3rd ed. (1922) |
| Color | graysingle sourceFord, Dana's Textbook of Mineralogy, 3rd ed. (1922) |
Chemistry (calculated)
| Molecular weight | 397.94 g/molcalculated from the IMA formula |
|---|---|
| Composition (wt%) | Na 5.78%, Al 20.34%, P 15.57%, O 56.29%, H 2.03% |
Classification
| Nickel-Strunz (10th) | 8.DL.10Wikidata (CC0) |
|---|---|
| Nickel-Strunz (9th) | 8.DL.10Wikidata (CC0) |
| Dana (8th) | 42.7.8.2Wikidata (CC0) |