(a) "Solid mineral" means any mineral other than crude oil and natural gas. Sulfur produced from natural gas shall be considered an element of the natural gas stream.
(b) "Supervisory personnel" means generally employees who direct and control the work of other employees and whose duties can still be distinguished as either relating to mining or processing.
(c) "Depreciation" means depreciation as actually determined and used by the taxpayer, in accordance with generally accepted accounting principles, for financial statement purposes. This depreciation is commonly referred to as book depreciation.
(d) "Pound" means 16 ounces avoirdupois.
(e) Ton" means short ton or 2000 pound avoirdupois.
011-6 Wyo. Code R. § 6-4a