Chalcedony from Cerro de Potosí (Cerro Rico), Potosí (Potosí Municipality), Tomás Frías Province, Potosí, Bolivia
Bolivia | |
| Petrov, Alfredo (n.d.) Personal Communication. |
| Lindgren, W. and Creveling, J.G. (1928) The ores of Potosi, Bolivia. Economic Geology, 23, #3, 233-262. |