Not a lawyer, but whether a deed conveys a mineral interest or a royalty interest is material. Since a mineral interest carries the right to negotiate leases, receive bonus payments and royalty payments, and a royalty interest only the right to receive royalty payments if there is production, the nature and the amount of the interest can be a big issue.
You didn’t mention the State. In Texas there has been a lot of case law involving whether the wording of a deed reserved minerals, or royalty, and many times the simple word “of” made a big difference in the fractional interest involved.
Thanks Dusty! I was afraid that something like this might be the case. The property is in TX . . . Pecos County to ne exact. I may need an attorney who is well versed in this case law.