To clarify, ideally, an appraisal is done at probate with an effective date as of the date of death. The prices for oil, gas and NGLS from the known producing wells, permitted wells and current leases are taken into account-so some possible uplift may be considered for the pending wells. If you do an appraisal much later, the sales from nearby minerals are generally used instead, often resulting in a lower value “as of date of death” because not as much data is available. Two appraisers have explained it to me this way. I would suggest talking to one to confirm.
As to the mineral deed, that sounds odd. Every deed I have has the exact description on it. What you may mean is that the probate listing of the minerals and their description is used instead of issuing new mineral deeds. The probate documents are the title documents. Again, they should have the descriptions as exactly as they can be traced. You have to know what you own. Perhaps one of the attorneys can elaborate as to the official answer.