Chalcedony from selected localities.
USA | |
| U.S. Geological Survey (2005) Mineral Resources Data System: U.S. Geological Survey, Reston, Virginia. |
NBMG Bull 78 Geology and Mineral Deposits of Esmeralda County, Nevada; U.S. Geological Survey (2005) Mineral Resources Data System: U.S. Geological Survey, Reston, Virginia. | |
U.S. Geological Survey (2005) Mineral Resources Data System: U.S. Geological Survey, Reston, Virginia. |