The Calumet Mining and Refining Company records (1927-1980s) contain information about several mining plants throughout Utah and Nevada. It also has information about mined materials and mining methods. Many of the materials also pertain to the Combined Metals Reduction Company.

The Combined Metals Reduction Company records (1913-1962) is a grouping of files, books, reports, ledgers, and papers pertaining to the development of the mining industry in Pioche, Nevada from 1920-1950.

Edward Harrison Snyder (1889-1967) was a member of the Snyder family who promoted mines in Utah, Idaho, and Nevada and were pioneers in various areas of metallurgy. In addition to participating in the family business of W.F. Snyder and Sons, E.H. Snyder was president of the Combined Metals Reduction Company in Salt Lake City, Utah. This collection contains images of the Snyder family and of Snyder's career in mining, particularly in the area of Pioche, Nevada.