North Dakota possesses significant concentrations of rare earth elements, primarily found within its extensive lignite coal deposits. While the precise rare earth minerals are not specifically named in public geological findings, the state's Geological Survey has identified areas with high rare earth element enrichment.
Discovery and Geological Context
The North Dakota Geological Survey has identified significant rare earth and germanium enrichment within lignite layers. One notable discovery is found beneath a thirty-foot-thick, brightly colored interval of rocks known as the Rhame bed. This particular Rhame bed enrichment is situated approximately 1,000 feet stratigraphically below an earlier, similar discovery of critical mineral enrichment found in another similar rock interval. These discoveries highlight the potential for critical mineral recovery from the state's vast lignite resources, particularly in southwestern North Dakota.
Lignite, also known as brown coal, is a soft, combustible sedimentary rock that forms from naturally compressed peat. In North Dakota, these deposits are extensive and have been identified as potential sources for these valuable elements.
Understanding Rare Earth Elements (REEs)
Rare earth minerals are typically mineral deposits that contain significant concentrations of a group of 17 chemical elements known as Rare Earth Elements (REEs). These elements are crucial for various high-tech applications, including electronics, renewable energy technologies, and defense systems.
The 17 Rare Earth Elements include:
Category | Rare Earth Element (Symbol) | Common Uses |
---|---|---|
Light Rare Earths (LREEs) | Lanthanum (La) | Optics, batteries, catalysts |
Cerium (Ce) | Polishing, catalysts, self-cleaning ovens | |
Praseodymium (Pr) | Magnets, yellow-orange pigments | |
Neodymium (Nd) | Powerful magnets, lasers | |
Promethium (Pm) | Not naturally occurring, research only | |
Samarium (Sm) | Magnets, nuclear reactors | |
Heavy Rare Earths (HREEs) | Europium (Eu) | Phosphors (TV/monitor screens) |
Gadolinium (Gd) | MRI contrast agents, magnets | |
Terbium (Tb) | Magnets, green phosphors | |
Dysprosium (Dy) | Magnets, lasers | |
Holmium (Ho) | Lasers, magnets | |
Erbium (Er) | Fiber optics, lasers | |
Thulium (Tm) | Lasers, portable X-ray devices | |
Ytterbium (Yb) | Lasers, stainless steel | |
Lutetium (Lu) | PET scans, catalysts | |
Associated Elements | Scandium (Sc) | Aluminum alloys, fuel cells |
Yttrium (Y) | Phosphors, superconductors |
The "enrichment" found in North Dakota's lignites indicates the presence of these elements in higher-than-average concentrations, making them a potential resource for future extraction.
Significance for North Dakota
The discovery of rare earth element enrichment in North Dakota's lignite beds holds significant promise for the state and national interests:
- Economic Diversification: It could provide a new avenue for economic development beyond traditional agriculture and oil and gas.
- Supply Chain Security: Developing domestic sources of rare earth elements can reduce reliance on foreign imports, strengthening critical mineral supply chains.
- Technological Advancement: These elements are vital for a wide range of modern technologies, from smartphones and electric vehicles to defense systems.
- Research and Development: The findings encourage further research into efficient and environmentally sound methods for extracting these valuable elements from lignite.