[PIF]

Procellarum KREEP terrane (PKT) — a concentration of potassium (K), rare earth elements (REE), phosphorus (P), along with heat-producing elements like thorium.

—
Well now we know what all those alien mining operations are going after.

[Verginius Rufus]

So that’s what KREEP is. Sam Ervin’s Senate committee kept talking about it in 1973.