Glauconite from Gunnison County, Colorado, USA
USA | |
| Eckel, Edwin Butt , Cobban, Robert R., Mosburg, Shirley K., Foord, Eugene E. (1997) Minerals of Colorado. Fulcrum Publishing. |
| Caine, J.S., Manning, A.H., Berger, B.R., Kremer, Y., Guzman, M.A., Eberl, D.D., and Schuller, K. (2010): USGS Open-File Report 10-1008 |