Gypsum from Hot Spring County, Arkansas, USA
USA | |
| Rocks and Minerals, (2001) 76:257 Rocks and Minerals, (1976) 51:495-507 |
| Scull(1959). Rocks & Min.:63:108 |
Henry Barwood - unpublished (2010) | |
Karl Estes (1998) Mineral News, 14, #5, 8-10. | |
Rocks and Minerals, (1976) 51:495-507 R&M 67:6 p402-404 |