Section 27-7-17(1)(g) provides that there shall be allowed as a deduction in computing taxable income in the case of mines, oil and gas wells, other natural deposits and timber, a reasonable allowance for depletion and for depreciation of improvements, BASED UPON COST, including cost of development, not otherwise deducted, or fair market value as of March 16, 1912, if acquired prior to that date.
35 Miss. Code. R. 3-05-05-100