So gravel is a mineral that has been defined as running with a surface right, unlike coal or oil and gas.
If you own acreage with gravel you get to sell it even if the mineral rights are retained by someone else.
However, if the Feds claim all minerals under your private land, then you don't get the gravel.
If the Feds have only the coal, then the private surface owner can sell the gravel, if the Frds have the oil and gas and not the coal (unusual but possible) then the private owner can sell the gravel.......
That is fun to explain to a landowner who figured he could sell his gravel.
Be careful with "Federal Mineral Rights!"
You need to look specifically at the "authority" (Act of Congress) recited in the Original Federal Patent which reserved the Mineral Estate. There are/were several specific Acts, and depending on the Act (authority), the "answer" changes. The Stock Raising Homestead Act of 1916 is most often encountered round these parts, BUT other Acts can (and do) come into play.
Loyal
The famous supreme case in, I think, 2004 pretty much sealed this one. The landowner has the w2 of sec6. Lot 5 has about a 1/3 of the gravel and Fed coal. Lot 6 has the bulk of the gravel and fed all minerals, so they are claiming the gravel.
