Muscovite from selected localities.
USA | |
| [var: Sericite] US Dept. Of Int. Bur. of Mines ROI #6885 (1967), Williams, R.L.:25. |
| Rocks & Min.: 17:344. |
USA | |
| [var: Sericite] US Dept. Of Int. Bur. of Mines ROI #6885 (1967), Williams, R.L.:25. |
| Rocks & Min.: 17:344. |