Records consist predominantly of interoffice correspondence (1903-1935) between the mine offices in Philipsburg and the home office in St. Louis. Correspondents include David Jankower, general superintendent; John R. Lucas, Montana agent for the company; and corporate officers Paul A. Fusz, Charles G. Ewing, George Zehnder, and L.M. Rumsey Jr. In addition there is general correspondence (1903-1929) with the Swiss factory, foremen at the mines, contractors building the flume, government agencies, and others. Court papers consist of an appeal of a United States Land Office order. Employment records include time sheets and time checks (1912-1930). Financial records include a letterpress volume (1906-1912) containing a variety of records; and scattered bills, freight bills, orders, etc. Legal documents (1903-1907) consist of mineral applications and an affidavit of lease. Organizational records consist of articles of incorporation (1901) copied from records of the Secretary of State's Office. Production records include reports (1912) on flume construction and reports (1911, 1914) on shipment of sapphires.