This collection consists of three subgroups. The W.C. Giebel Subgroup consists of incoming and outgoing correspondence (1955-1978) dealing with mining and ore processing matters, patents, political and monetary policy, and the history of Nelson, Wisconsin; financial records (1946-1978); legal documents (1969, 1974); maps (undated); production records (1947-1977) from several mining properties, including the Gulf Claim and the Star Mine of Neihart, the Hilger Ore Milling Company of Lewistown, and the Tamarack Mine near Sheridan; writings (1959-1962) on monetary policy; clippings; and miscellany. The Green-Campbell Mining Company Subgroup contains financial records (1937-1970); legal documents (1969); production records (1937-1942); an oversize map (circa 1939) of the workings of the Eagle Shaft; and miscellany. The Montana Western Mining Company Subgroup consists of a time book (1943-1944) and other financial information; and by-laws (1943). Printed material has been transferred to the Library.