uranium. The severance tax is imposed at the following rates on the taxable value determined under Section 7-26-4 NMSA 1978 of the following natural resources: A. potash 2 1/2% B. copper 1/2% C. timber 1/8% D. pumice, gypsum, sand, gravel, clay, fluorspar and other nonmetallic minerals 1/8% E. lead, zinc, thorium, molybdenum, manganese, rare earth and other metals 1/8% F. gold and silver 1/5% History: 1953 Comp., § 72-18-5, enacted by Laws 1977, ch. 102, § 7; 1984, ch. 84, § 2.