| Mineral | WALPURGITE |
| Chemistry | (BiO) 4 (UO 2 )[AsO 4 ] 2 · 3H 2 O |
| Color | Yellow orange-Yellow |
| Luster | Adamantine |
| CrystalSystem | Triclinic |
| CrystalHabits | include platy elongated crystals often aggregated and twinned.Also as crusts, fibrous and earthy. |
| Fracture | perfect. |
| Hardness | 3½ |
| Characteristics | Radioactive, non-fluorescent and cleavage sheets are surprisingly brittle. |
| Indicators | color, crystal habit, high density, non-fluorescence, radioactivity and associations. |
| DensityNote | well above average for translucent minerals |
| IMAStatus | Approved - Published prior to 1959 (pre-IMA) - Gra |
| Discovered | 1871 |
| CellParameters | a = 7.13b = 10.44c = 5.49 α=101.6°β=110.82°γ=88.28° |
| Ratio | a:b:c = 0.683 : 1 : 0.526 |
| OpticalType | Biaxial (-) |
| RI | n α =1.871 - 1.910 n β =1.975 - 2.000 n |
| Birefringence | δ=0.134 - 0.150 |
| SurfaceRelief | Very High |
| TypeLocality | Walpurgis Flacher vein Weißer Hirsch Mine ( Shaft 3) Neustädtel Schneeberg District Erzgebirge Saxony Germany |
| Strunz | 7/E.10-20 7 : PhosphatesArsenatesVanadates E : Uranylphosphates and uranylvanadates with [UO2]2+ - [PO4 | AsO4]3- and [UO2]2+ - [V2O8]6- 10 : Asselbornite - Walpurgite series |
