CREEDITE: Chihuahua, Mexico (0.96)
Creedite is one of the very rare minerals known to collectors. It may well be that less than a dozen creedite gems have ever been cut. The mineral itself is rare, cuttable crystals even more so. These would be colorless or purple and from the Mexican occurrence. The hardness is too low for wear - strictly a collector gem.
Creedite Value
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Creedite Information
| Data | Value |
| Name | Creedite |
| Crystallography | Monoclinic. Crystals short, prismatic; also radial clusters. |
| Colors | Colorless, white, rose to lilac or purple. |
| Luster | Vitreous. |
| Hardness | 4 |
| Density | 2.71 -2.73 |
| Birefringence | 0.024 |
| Cleavage | Perfect 1 direction. Fracture conchoidal. Brittle. |
| Dispersion | Moderate |
| Stone Sizes | Faceted gems very small, usually less than 1-2 carats. Private Collection: 0.96 (purple, Chihuahua). |
| Luminescence | Medium white to cream color (SW); bright white to cream (LW). |
| Spectral | Not diagnostic. |
| Formula | Ca3AI2(SO4)(F,OH)10 • 2H2O. |
Optics: a= 1.461; β = 1.478; γ= 1.485. Biaxial (-), 2V= 64°.
Darwin, California; Granite, Nevada. Colquiri, Bolivia.
Creede, Colorado: in cavities in rock with fluorite and barite.
Wagon Wheel Gap, Colorado: in a fluorite-barite mine.
Santa Eulalia, Chihuahua, Mexico: in crystals up to 1 inch long, gemmy.
Comments: Creedite is one of the very rare minerals known to collectors. It may well be that less than a dozen creedite gems have ever been cut. The mineral itself is rare, cuttable crystals even more so. These would be colorless or purple and from the Mexican occurrence. The hardness is too low for wear – strictly a collector gem.
Name: Occurrence in the Creede Quadrangle, Colorado.
