Chert from Montana, USA
USA | |
| Rocks & Minerals 81:340-355 |
| (2005) Mineral Resources Data System (MRDS), US Geological Survey. |
| Barrick Gold Corporation |
| (2005) Mineral Resources Data System (MRDS), US Geological Survey. |
Jay Ellis Ransom,1974, Gems and Minerals of America | |
(2005) Mineral Resources Data System (MRDS), US Geological Survey. | |
Jay Ellis Ransom,1974, Gems and Minerals of America |