There’s a discussion forum on this site that you can read:
There are also other definitions of “royalty acres” in other states (sometime more than one in a given state):
(This latter may require registration to read.)
The real question when valuing your mineral and royalty interests is how much revenue will they generate? With regard to unleased mineral interests, how much can I expect to receive in bonus payments when and if my interest is leased. This is highly dependent on where they are and whether they are in a “hot” area (like the Permian). Since bonuses for oil and gas leases are usually quoted “per net mineral acre” this is a useful way to think of the value of unleased minerals for leasing purposes.
If the minerals are already leased, I prefer to use decimal or percentage shares of production revenue. If you can estimate how oil or gas revenue will be produced over how long a period of time, and you know your royalty decimal or percentage interest in that revenue stream, you can arrive at a “net present value” of the estimated future cash flow. Investors use this method all the time in valuing all kinds of investments. If you are contemplating a sale of your royalty interest, it might be worthwhile to get an estimate of this to compare to the offer you’ve received. You’d probably need a petroleum engineer to estimate future production rates. You also need to make estimates about future oil and gas sales prices, which are historically pretty volatile. A given tract of land may produce multiple different revenue streams from multiple different wells and your decimal share of the wells may differ.
When presented with an offer to purchase your minerals or royalties, the first question should be: What do they know that I don’t know?