|
USA | |
| Eckel, Edwin Butt , Cobban, Robert R., Mosburg, Shirley K., Foord, Eugene E. (1997) Minerals of Colorado. Fulcrum Publishing. |
| D. Slade collection |
| Eckel, Edwin Butt , Cobban, Robert R., Mosburg, Shirley K., Foord, Eugene E. (1997) Minerals of Colorado. Fulcrum Publishing. |
| Muntyan, Barbara, Muntyan, John (1985) Minerals of the Pikes Peak Granite [Colorado]. The Mineralogical Record, 16 (3) 217-230 |
| Eckel, Edwin Butt , Cobban, Robert R., Mosburg, Shirley K., Foord, Eugene E. (1997) Minerals of Colorado. Fulcrum Publishing. |
Popes Bluff, Colorado Springs Area, El Paso County, Colorado, USA