Chalcedony from selected localities.
USA | |
| U.S. Geological Survey, 2005, Mineral Resources Data System: U.S. Geological Survey, Reston, Virginia. |
| Wilson,W.F and McKenzie,B.J(1978)Mineral Collecting Sites In North Carolina;NCGS Information Circular 24 |
U.S. Geological Survey, 2005, Mineral Resources Data System: U.S. Geological Survey, Reston, Virginia. | |
| Rocks & Min.: 17:62 |