Chalcopyrite from Crawford County, Wisconsin, USA
USA | |
| Heyl, A., A. F. Agnew, E. J. Lyons & C.H. Behre Jr. (1959), The geology of Upper Mississippi Valley Zinc-Lead District: U.S. Geological Survey Prof. Paper 309, 310 p. |
| R&M 73:11-12 pp 378-399 Wisconsin Mineral Locality Index |