My uncle recently passed and he left mineral deeds in three counties in OK and one county in Texas. Eventually the heirs will sell these rights, so it is helpful to know their value for tax purposes. Is there a website that can help with the valuation? Or perhaps a formula to use?
The most reliable way is to get a certified petroleum engineer to give a value for estate purposes. The estate can pay for the evaluation. No easy way to do it that the IRS will take.