Outside developed oil or coal plays, severed mineral estates in the US are the exception, not the rule. Also, to the point above, those severed mineral interests are almost always privately held.
Re:Norweigan oil fund
by kevin_thibedeau on Thursday August 01, 2019 @01:55PM
(#20586456)
Unless they happen to be on "sovereign" indian reservation land.
Usually where there are significant amounts of minerals, there are separate mineral rights. Mineral rights trump surface ownership, and usually the rights were sold off decades or centuries ago. If you find something under your property, it probably doesn't belong to you.
Also, state laws vary in weird ways. Should you find gold in New York, it's the property of the state.