Perhaps a dozen years ago China got mad at Japan, and cut off its supply of rare earth elements. There was suddenly a mad scramble for developing rare earth element mines.
There's a variety of environments that rare earths can be mined from. One of these is from soils which have naturally concentrated rare earths, such in Kachin State in Myanmar. There is a similar mineable hill in Texas, US, called Round Top.
Years ago a bunch of mineable sites were developed, largely on paper. All they required was a pile of money to develop, typically hundreds of millions to a few billion dollars. While everyone in the world was screaming for more rare earths to be mined, nobody was putting up the money to actually start mining.
Round Top saw a similar fate. As the property was just sitting there idle, the owners of the property kept adding to a list of economic minerals and elements found on the property, and developed "flow sheets" of mining processes to economically extract them, to attract investors. All of the other potential mines were doing the same, so there were plenty of potential mines that only needed a billion dollars to start production. And the seed money almost never appeared.
Round Top had a partnership with a college, which I think was University of Texas, to develop the mine.
Round Top's ownership appears to have been legally restructured over the years. Like other rare earth companies, they developed a linkage with precious metals mining. This appears to be a matter of raising start-up money.
The US Government, in the last few years, provided a relatively small amount of
seed money to jump start the process of rare earth element mining that's immune from China's influence. So the US Government may nix this suggestion. China and the US could co-develop methods to ecologically friendly mine rare earth elements from soil deposits. Let's save the environment!