The Fort Union Trading Post Collection. This is a catalog of trade beads excavated at the Fort Union historical site approximately 2 miles above the confluence of the Missouri River and its tributary - the Yellowstone, near the North Dakota and Montana state line. Fort Union was established in 1829 as the headquarters of the American Fur Company's newly formed branch known as the Upper Missouri Outfit.
In 1968 excavation started and before completion over 38,000 glass, bone and shell beads were recovered, along with large number of other artifacts.
This is a significant source of data regarding trade with the Blackfeet, the Crow, Souix, Cree and Metis.