Clay from Midcontinent Rift, USA
USA | |
| (2005) Mineral Resources Data System (MRDS), US Geological Survey. |
| Rocks & Minerals (1943): 18: 326. |
USA | |
| (2005) Mineral Resources Data System (MRDS), US Geological Survey. |
| Rocks & Minerals (1943): 18: 326. |