Cerussite , white lead ore - a mineral , lead carbonate , valuable lead ore. The name comes from other Greek. κηρός - wax, lat. cerussa - whitewashed, in color similarity (formerly cerussite was used in cosmetics as powder ), given in 1845 by the Austrian mineralogist W. Geidinger .
| Cerussite | |
|---|---|
 Zerussite from France | |
| Formula | PbCO 3 |
| Physical properties | |
| Colour | Gray, brownish, often colorless, sometimes black |
| Trait color | White |
| Shine | Bold to Diamond |
| Transparency | Transparent to translucent |
| Hardness | 3.0-3.5 |
| Cleavage | Imperfect to clear |
| Kink | Crusty, uneven; very fragile |
| Density | 6.46-6.57 g / cm³ |
| Syngonia | Rhombic |
| Refractive index | 1,804-2,078 |
Content
Properties
Birefringence −0.274, dispersion 0.051, pleochroism is absent, the absorption spectrum is not interpreted. Luminescence is usually yellow, often bright, sometimes whitish, sometimes absent. The crystals are tabular, columnar or needle, often twin. The aggregates are dense, granular, characterized by kidney-like and sheaf-like discharge.
The earthy variety of cerussite is “lead earth” .
Fine-crystalline mixture of cerussite with galena - “black lead ore”.
It occurs in the oxidation zone of sulfide polymetallic deposits .
Deposits
Places of manifestation - Germany , Zimbabwe , Australia ( Broken ), USA ( Arizona , California , New Mexico , Colorado ), Poland ( Lower Silesia ), Russia (Eastern Transbaikalia , Altai ), Kazakhstan . Crystals suitable for cutting are found in the Czech Republic , Italy ( Sardinia ), Austria ( Bleiberg ), Scotland , Namibia ( Tsumeb ), USA ( Pennsylvania , the southern part of the Rocky Mountains ).
You can confuse faceted cerussite with diamond and other colorless and brownish jewelry stones .
Literature
- Schumann V. The world of stone. Precious and ornamental stones. - M .: Mir, 1986.P. 192.