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 Sandstone Ranch Collection is comprised of bank statements, letters, correspondence, and photographs relating to the Wilson family from 1907 to 1941. The collection includes information about the financial aspect of the Wilson Ranch, later renamed the Sandstone Ranch, located outside of Las Vegas, Nevada. The collection also includes information about the personal lives of those working on the including contracts about grazing cattle, selling cattle, and appropriation of water.

The Squires Family Photographs document the Squires Family and the development of the Las Vegas Valley in Nevada from approximately 1860 to 1980, with a bulk of the photographs depicting people and events from 1900 to 1950. The photographs depict the Euro-American settlement and growth of Las Vegas, Nevada; traveling and exploration of Southern Nevada and the Southwestern United States; the Hoover (Boulder) Dam and the Colorado River; clubs and social groups; and the Squires Family, especially prominent newspaper editor and publisher Charles Pember (C. P. or “Pop”) Squires, Delphine “Mom” Anderson Squires, and their children.