Location
Ionic clays
- Currently mined only in China, but resources depleting
- 27% of global REE production (incl. illegal mines)
Hard rock
- China dominates (>85%) global production of REEs
REE Assemblage
Ionic clays
- Koppamurra could be a new single source of the REEs (Nd, Pr, Tb, Dy) used in rare earth permanent magnets
Hard rock
- Monazite or bastnaesite ores which are typically higher in [light] REEs
Scale
Ionic clays
- Typically smaller tonnage but higher value products
Hard rock
- Typically require significant scale for economic viability
Exploration
Ionic clays
- Resources can be defined inexpensively and rapidly given shallow drilling using aircore, auger, push-tube core
Hard rock
- Similar to other hard rock base metals requiring substantial drilling, geochemistry, geophysics etc
Mining
Ionic clays
- Shallow free digging material with low strip ratio
- Stripping and progressive rehabilitation
Hard rock
- Drill and blast with significant mining fleet
- Higher strip ratios or underground mining
Processing
Ionic clays
- Simple metallurgy; clay is washed with a desorption agent to recover REEs
- No toxic chemicals nor radioactive waste streams
Hard rock
- Strong acids with high temperature +/- pressure
- Radioactive tailings