Sapphire from
USA | |
| Mining Journal, London, Vol. 329, No. 8437, July 11, 1997, p. 27. |
| USGS Bull 269 |
| Berg, R.B. 2007 "Sapphires in the Butte-Deer Lodge Area, Montana" Montana Bureau of Mines and Geology, Bull. 134 |
USA | |
| Mining Journal, London, Vol. 329, No. 8437, July 11, 1997, p. 27. |
| USGS Bull 269 |
| Berg, R.B. 2007 "Sapphires in the Butte-Deer Lodge Area, Montana" Montana Bureau of Mines and Geology, Bull. 134 |