9. A tax on mineral rents may be made neutral as to discovery as well as to conservation.
Herfindahl and Vickrey have expounded the intertemporal neutrality of a tax on net realized mineral rent. Their exposition has been in terms of a net value above costs, where revenues and costs were assignable to individual years. Steele has intimated the difficulties &f this concept where heavy initial capital costs must be spread over many years, and M