Rob Lavinsky, iRocks.com – CC-BY-SA-3.0 [CC-BY-SA-3.0], via Wikimedia Commons
Cut boleite is strictly for collectors, since it is soft and very rare. Faceted gems of any transparency should be considered among the rarest of all gemstones. The color is so attractive that any available stones would be quickly snapped up by collectors.
| Data | Value |
|---|---|
| Name | Boleite |
| Crystallography | Tetragonal. Pseudocubic. Crystals usually cube shaped, sometimes modified by other faces, and in parallel growths. |
| Refractive Index | 2.03-2.05 |
| Colors | Indigo blue to Prussian blue, blackish blue. |
| Luster | Vitreous, pearly on cleavage. |
| Hardness | 3-3.5 |
| Fracture | Uneven |
| Specific Gravity | 5.05 |
| Birefringence | 0.020 |
| Cleavage | Perfect 1 direction, good 1 direction |
| Luminescence | None. |
| Luminescence Present | No |
| Transparency | Transparent to opaque. |
| Absorption Spectrum | Not diagnostic. |
| Formula | Pb9Ag3Cu8Cl21(OH)16 · H2O |
| Pleochroism | None. |
| Optics | o = 2.05; e = 2.03. Uniaxial (-). |
| Optic Sign | Uniaxial - |
| Etymology | Named after the type locality, Boleo, Santa Rosalia, Baja California, Mexico. |
| Occurrence | Secondary mineral in Cu and Pb deposits. |
OPTICS: o = 2.05; e = 2.03
Uniaxial (-)
OCCURRENCE: Secondary mineral in Cu and Pb deposits.
Chile; Broken Hill, N.S.W., Australia
Boleo, Baja California: magnificent single crystals and groups on matrix, with single crystals up to nearly ½ inch.
COMMENTS: Cut boleite is strictly for collectors, since it is soft and very rare. Faceted gems of any transparency should be considered among the rarest of all gemstones. The color is so attractive that any available stones would be quickly snapped up by collectors.
NAME: Boleo, Santa Rosalia, Baja California, Mexico.
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