Test it first. I think the owner has to file a quit claim deed. I think you then file over it. However I just find them and evaluate them. You need to talk to someone in the BLM.
For example; There are some of these mines that are Superfund sites waiting to happen. We found one in Co years ago- gold mine claim that had many barrels of Cyanide leaking into acres above a large town.
You wouldn't want to get saddled with a 450 million dollar clean up.
on the other hand, I met some guys that did extremely well on a claim in Montana
Why do you want to purchase a claim? For a place to camp? For a hobby? If it’s either of those two reasons, consider the much cheaper alternative of joining a prospecting club that already owns a bunch of claims.
Most people that ask this question with the intent to “make money” gold mining are about to make a whole bunch of money for other people (people that sell claims, lawyers, feds, companies that sell mining equipment, people that sell advice, etc...).
Yeah, the process of buying a claim is one thing, the other is what are you planning to do with it? Actually mine it or do you think you can use it for recreation?
There are also different types of claims. There are current claims that are just mining claims that are for mining giving you the right to extract minerals from but you do not own the surface land and then there are the old claims that were “patented”. The old patented claims are actually land that you buy and own and can do what you wish with.
There is a third one. Up until 1955 under pl 167, claims had surface rights. At the separation there were valid existing rights on claims that met the criteria. They still exist but can be a pain to work with the federal agencies- especially the recent young employees.