Look to the granting clause… It generally has language like, “Grantor does hereby grant, set over and convey to Grantee all right, title and interest…”
If the blanket language is in the granting clause, it would be a lot easier to assert that was the intention of the parties. What was the agreed transaction? X number of dollars for your interest in a defined area or X dollars for everything you own, whether accurately described or not?
If the Mineral Deed language does not reflect the agreement of the parties, don’t sign the Mineral Deed. That’s my $.02 worth.
Best of fortune,
Buddy Cotten