HUREAULITE: Pala County, California (~3 inches across)
The colors are rich and lively, but the mineral is too soft for wear. Hureaulite is a collector gem and is very rare even in cabochon form.
Hureaulite Value
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Hureaulite Information
| Data | Value |
| Name | Hureaulite |
| Crystallography | Monoclinic. Crystals prismatic up to 3 cm, tabular; massive; compact. |
| Colors | Pale rose, violet-rose, yellowish, red-orange, orange-red, brownish orange, yellowish to reddish brown, gray, colorless. |
| Luster | Vitreous to greasy. |
| Hardness | 3.5 |
| Density | 3.19 |
| Birefringence | 0.012 |
| Cleavage | Good 1 direction. Fracture uneven. Brittle. |
| Stone Sizes | Massive material suited only for cabochons. No faceted gems have been reported to date, but facetable material likely exists and one day will be cut. |
| Luminescence | None |
| Spectral | Not diagnostic. |
| Formula | Mn5(PO4)2[(PO3)(OH)]2 · 4H20. |
| Pleochroism | Colorless/pale rose to yellow/reddish yellow-brown. |
Optics: a = 1.637-1.652; β= 1.645-1.658; γ= 1.649-1.663.
Biaxial ( – ), 2V= 75°.
Occurrence: In phosphate masses in granite pegmatites. Branchville, Connecticut: North Groton, New Hampshir; South Dakota.
Haute Vienne, France; Portugal; Germany: Poland, Pala, California: orange masses.
Comments: The colors are rich and lively, but the mineral is too soft for wear. Hureaulite is a collector gem and is very rare even in cabochon form.
Name: After the locality, Hureaux, France.
