The appraiser should be advised that in eminent domain proceedings TxDOT, by law, is limited to acquisition of fee title excluding oil, gas and sulfur, and that the limitation of this law has been applied by TxDOT policy to acquisition of rights of way by negotiation.

On a partial acquisition involving a separate ownership of minerals which includes hard minerals, special handling is required if the hard minerals have or appear to have some economic value and if production thereof would require surface operations. Gravel, sand, caliche, and iron ore gravel, useful only for building and road construction purposes, are not regarded as minerals within the generally accepted meaning of that word. When the grantor reserves title to minerals, the reservation does not include these road-building items unless the grantor has expressly indicated such intent by specific reference to these items in the reservation.

Whenever possible the appraiser should use comparable sales that have transferred only the surface rights, rather than adjusting sales that include minerals. However, if it is necessary to use sales that require such adjustments, the appraiser should compare sales that included minerals with sales that excluded minerals in order to measure the adjustment by market data.