DESCRIPTION: These are occupation tax returns and net proceeds returns which were submitted by metalliferous mining companies and, by 1956, oil and gas companies, to the Tax Commission as the basis for assessment of taxes. Both types of returns identify the mine or well owner and mines or wells involved. The occupation tax is based on the gross value of production. Net proceeds taxes are based on the value of mineral deposits, determined by calculating sales less business deductions over one or more years. The necessary information on production and sales and calculations are part of the respective returns.

In 1937, the legislature enacted a law requiring metalliferous mine owners or producers to pay an occupation tax equal to a small percentage of the gross amount received for, or the gross value of, ore sold. The occupation tax statements identify the mine owner and address, the mine name and location, and a description of the mine; the weight produced, sold, and not sold; the disposition of the ore sold; and the gross proceeds from the sale plus any other bonuses; certain deductions such as smelter treatment, refining, sampling, and transportation charges; legal exemption; and finally the amount on which the occupation tax is based and the calculation of the actual tax. A notarized affidavit appears at the bottom of the form, attesting to its validity. In 1955, the legislature added oil and gas wells to the operations required to pay an occupation tax and similar occupation tax statements were added showing barrels or cubic feet produced, sold, or stored and the related values.

Although net proceeds were used to calculate the value of a metalliferous mine since 1896, they were part of other series of returns until 1938. With the introduction of an occupation tax, they began to be filed with this series. Net Proceeds statements identify the mine owner and address, the mine name and location, and a description of the mine; the weight produced and its value; then gross proceeds plus certain additional proceeds or purchaser deductions and the resultant total amount received; various deductions (e.g. mining operations by owner and lessees, milling and concentrating costs, other reduction costs, transport costs, salaries, state and local taxes, machinery and improvement costs, etc.); the resultant net proceeds; and finally the value of the mine based on a multiple of the net proceeds. These too have a notarized affidavit at the bottom of the form.