As far as the OP, I understand one of the metals under discussion is lithium. That’s not a rare earth element, but is used a lot in batteries. But there is a lithium mine being started near the Nevada-Oregon border. It’ll take some years to get in production.
Also there’s supposed to be plants extracting lithium from geothermal brines in the Salton Sea and other areas. They’ve been talking about this for quite a while, but AFAIK, none have been produced yet.
Firstly - REEs prefer to stay in melt and not go into most common minerals, so they’re concentrated in certain late-stage igneous rocks - which are geographically comparatively rarer, like carbonatites and pegmatites.
Then, in terms of secondary deposits - they tend not to go into solution easily, so they wind up as heavy mineral sands which require particular depositional environments to form viable deposits. Or they end up in clay deposits because of their relative insolubility.
‘Reserves’ of ores are sources that are either being mined, or known about. There will be many many more sources that haven’t yet been discovered, so it’s not an exact indication of where they are located. They’re only going to look in places where extraction is viable.
Reserves are a very rubbery thing.
There are known reserves, proven reserves, economic reserves, just to start.
“Gold in them thar hills” isn’t a reserve. But underlines why reserves are rubbery.
There is a disincentive for mining companies to invest explore too far into the future. Typically they need to obtain an exploration licence from the government. These cost money, have a timeout period, and require that exploration actually occur. Exploration costs money. If you actually find an economic reserve and wish to develop it, you need a production license and negotiation of the royalties etc. if you find something and don’t want to proceed with production you risk your rights to the reserve being lost. Countries may be unhappy that a potential economic input is sitting doing nothing. A lot depends on the resource and the county.
The upshot is that proven and know reserves are often only ever about ten years production. For niche minerals this may not apply since with a very few known reserves and very limited demand the general flow of operations doesn’t happen.
Even absent government regulations like that, there still wouldn’t be an incentive to explore too far into the future. It costs money to do that exploration, and there’s no sense in spending money now if you’re not going to be starting the profitable part for more than a decade.
Agree in general.
The only possible exception is if there’s genuine belief in the industry that the as-yet-unlocated resources are absolutely rare around the world. So several competing mining companies would want to find, and lock in for themselves, whatever is out there to be found. Before the other guys do so.
Much like developers buying up all the developable land on a tropical island because once it’s sold, they can’t get more. They might sit on it as a non-performing asset for years or decades before they invest in converting wilderness into a resort. All while booking depreciation on what’s actually an appreciating asset.
That was sort of the gist of my original question.
I’m not a geologist or minerologist, but the US is a large country with a lot of different terrains.
So I’d be somewhat surprised if there weren’t viable sources available?
Of course economics and environmental concerns are a different matter…