The Tonopah Mining Company Records derive from the office of the company’s general manager in Tonopah, Nevada and consist of documents directly generated by its mining and milling operations from 1901 through 1941. The collection includes daily work reports, assay reports and certificates, employee time cards, invoices and receipts for mining equipment and supplies, monthly stores reports, and the company’s numerous insurance policies. Several of the company’s annual reports, including an original typescript copy of the 1907 annual report, are included in the collection. Additionally, select records from the company's subsidiary, Desert Power and Mill Company, as well as the Tonopah and Goldfield Railroad, which include overcharge claims, freight and repair bills, and delivery receipts are included in the collection.

The Eberhardt and Aurora Mining Company Records (approximately 1869-1877) are comprised of the administrative records and financial documents of the mining company located in White Pine County, Nevada. The majority of the collection contains correspondence, but also includes several documents relating to the company's finances such as bills, receipts, cancelled checks, and bank statements.