The Anaconda Copper Mining Company Records consist of correspondence, court papers, financial and production records, legal documents, organizational records, subject files, and other materials for the company and many of its predecessor and subsidiary companies and departments. Among the major subgroups into which the collection is arranged are the General Office, the Big Blackfoot Milling Company, the Bitter Root Development Company, the Boston and Montana Consolidated Copper and Silver Mining Company, the Butte and Boston Consolidated Mining Company, the Colorado Smelting and Mining Company, the Diamond Coal and Coke Company, the Parrot Silver and Copper Company, the Reduction Department (Anaconda), the Trenton Mining and Development Company, the Tuttle Manufacturing and Supply Company, and the Washoe Copper Company. In addition, there are more than one hundred smaller subgroups (see Table of Contents). Unconnected with the primary mining, smelting and timber operations of the Company were several affiliated companies in the hotel and related fields; oil and gas development; water and townsite companies; and newspaper publishing. Subgroups for these include the Silver Bow Club, the Florence Hotel and the Montana Hotel; the West Dome Oil Company; the Anaconda Townsite Company and the Hamilton Water Company; and the Post Publishing Company and the Montana Free Press.

Among the more significant operations documented in this collection are the General Office, both in Butte and in Anaconda; the various subsidiary operations, both before and after their absorption into Anaconda; and the two large treatment plants, the Anaconda Smelter and the Great Falls Refinery. Among the subjects documented are the technical and economic details of the two smelters; the company's large lumber operations in the Missoula area; the company's coal mines; relations with employees; and treatment and recovery of tailings, including the related issue of air and water pollution. There is less documentation for the core mining operations in Butte.