[ETCM]

No, uranium is not scarce on Earth. It is a relatively common element in the Earth’s crust

Economically viable ore concentrations for mining are much rarer. High grade deposits like those in Kazakhstan are rare and valuable to someone wanting to produce enriched or highly enriched uranium.

[Bookshelf]

“Economically viable ore concentrations for mining are much rarer.”
That was the reason that Shinkelobwe, Belgian Congo, was such an important prize to be held by the USA during World War II.