The Charles S. Sprague and Benjamin Gill Papers on Nevada Mining (1904-1925) are comprised of various records from the mining companies owned and operated by businessmen Charles S. Sprague and Benjamin Gill who were active in the central Nevada boomtowns of Goldfield and Tonopah in the early twentieth century. Documents include correspondence, receipts and invoices, detailed records and copies of government legislative bills relating to the mining industry, and other business correspondence. Sprague's collection consists of his mining business correspondence dating from 1906 to 1925. Gill's papers are comprised of his business correspondence from 1916 to 1922.

The J. Ross Clark Photograph Collection (approximately 1900-1920) consists of black-and-white photographic prints and some corresponding negatives. Images depict J. Ross Clark, his wife Miriam Evans Clark, their grandson James Ross Clark II, and several unidentified individuals.