The most important materials in the collection are interoffice correspondence (1877-1881, 1885, 1893) between mining department superintendent Samuel A. Barbour and general manager Henry Knippenberg and other company officials. In addition there are outgoing letterpress volumes (1871-1886) of Noah Armstrong, J.W. Earl, Henry Knippenberg, George Conway, and others. There are employment records (1876-1922) including payrolls, time books, and payments charged to employees' accounts for store and boarding house; financial records (1875-1899) including bills, freight bills, journals, ledgers, supply records, and trial balances; minor legal documents; a minute book (1898-1906); and production records (1877-1895) include assay reports, mine timber books, ore receipts, and ore shipments. In addition there is an unsigned account (possibly by Benjamin F. White) or a prospecting trip in 1880 to Lion City.