But while the KREEP-rich samples brought back by the Apollo astronauts led researchers to believe that rare earth metals were abundant through the moon, recent gamma-ray spectrometer analysis has indicated that there’s far less rare-earth material on the moon than previously thought, and that’s it’s concentrated in specific areas. In other words, prospective moon miners should pick their landing site carefully.
Others, notably former Apollo 17 astronaut Harrison Schmidt, have suggested mining the moon for Helium-3, an isotope that’s relatively common on the lunar surface but extremely rare on earth. Helium is used for a variety of current purposes, including radiation detection and MRIs, but some believe it could also be used for nuclear fusion power. … Unfortunately, mining HE-3 is not so easy.
Read the whole thing. By the way, it’s true that we poor Earthlings are at risk of running out of Helium-3, which is useful for medical imaging, for detecting smuggled nuclear weapons material, and also as a potential fuel for next-generation fusion reactors. But the United States is mainly facing a looming Helium-3 shortage because of bureaucratic bungling. The Energy Department has inadvertently been selling off the isotope, a by-product of the nuclear-weapons program, six times as fast as it was being produced. Fixing that oversight sounds like a modest first step before we go off harvesting our lunar counterpart.