Columbite-Tantalite from selected localities.
USA | |
| USGS Proffesional Paper 265 |
USGS Profesional Paper 265 | |
| USGS Proffesional Paper 265 |
USGS Proffesional Paper 265 | |
Pearl, 1958. Colorado Gem Trails & Mineral Guide; USGS Proffesional Paper 265 |
USA | |
| USGS Proffesional Paper 265 |
USGS Profesional Paper 265 | |
| USGS Proffesional Paper 265 |
USGS Proffesional Paper 265 | |
Pearl, 1958. Colorado Gem Trails & Mineral Guide; USGS Proffesional Paper 265 |