The Montana Letterheads collection consists of various businesses in both Butte and Anaconda Montana throughout the late 19th and mid 20th centuries. The material includes: J.E Oppenheimer who was well known in the produce and cigar business; The Anaconda Copper Mining Company which was headquartered in Butte and was one of the largest copper mining companies of the century; The Standard Publishing Company; and The Butte Fair and Racing Association, which lists William Andrews Clark, Jr. as president and director, among many others.