Quartz from selected localities.
USA | |
| SDSMT Bull 18 Roberts and Rapp "Mineralogy of the Black Hills" |
SDSMT Bull 18 Roberts and Rapp "Mineralogy of the Black Hills" | |
| U.S. Geological Survey, 2005, Mineral Resources Data System: U.S. Geological Survey, Reston, Virginia. |
| [var: Amethyst] SDSMT Bull 18 Roberts and Rapp "Mineralogy of the Black Hills" |