Independent Geologic Reports
Rare earth enriched Phosphorus Apatite was known to exist in the related iron ore deposit as early as 1960s. As underground mine development progressed additional rare earth deposits were identified in the late 1970s, known as Breccia Pipes. Collaborative work was conducted by USGS, US Bureau of Mines and the State of Missouri's Department of Geologic Survey. Test work established successful methods for resource processing, recovery and concentration based on milling and gravity separation. Successful elemental extraction was conducted by independent researchers the 1990s.
- USGS Report 1
- USGS Report 2
- Missouri Department of Natural Resources Geologic Survey Report
- The United States Bureau of Mines
- Typical Independent Geologic Report 1
- Typical Independent Geologic Report 2