TL;DR: Lunar KREEP REE is a main entry in the 外星矿物知识引擎 database.
KREEP (Potassium, Rare Earth Elements, Phosphorus) terrains on the Moon contain elevated REE concentrations. While lower grade than terrestrial deposits, the absence of environmental regulations and co-location with other ISRU activities could make extraction viable.
Resource Type
Rare Earth Elements
Location
Lunar KREEP terrain (Mare Imbrium region, Oceanus Procellarum)
Estimated Quantity
Significant but poorly quantified
Extraction Method
Acid leaching or molten salt electrolysis of KREEP-rich regolith
Economic Value
High if terrestrial supply constrained; REEs worth $100-1000/kg