[pottertheotter]

As you said, rare earth elements aren't really rare--they are very abundant. But they are mixed in with themselves (there's 17 of them) and lots of other elements. Think of it like if you had 50 different colored sands and had huge amounts of all of them, then mixed them all up. The rarity is that you're not going to go through that sand and find a big patch of blue sand.

There's plenty of them, and all over the world. It's also important to separate the mining of rare earths from the processing/refining. 60% of REEs come from mines in China. But 90% of the processing is done in China (for some of them, heavy REEs, 100% of it is done there).

It wasn't always this way, but started to change in the 80s and 90s as Chinese firms were able to process rare earths at much lower costs. It was a mix of things--labor rates, lax standards, as well as state subsidies (the latter shouldn't be overlooked).

It's difficult to reopen processors, and starting up new ones requires a lot of time and money. We can do it, we just can't flip a switch and start it up. Also, China has developed a lot of new technology to do it and have export controls on the tech. Also, we have much more severe environmental standards these days that would make it even more difficult to get going.