A yellowcake boomtown is a town or community that rapidly increases in population and economics due to the discovery of uranium ore-bearing minerals, and the development of uranium mining, milling or enrichment activities. After these activities cease, the town "goes bust" and the population decreases rapidly. Yellowcake (uranium oxide) is partially refined uranium ore, called so because of its bright yellow color. Jeffrey City, Wyoming is considered a yellowcake boomtown whose "boom" began in 1957, and by 1988 the town had gone "bust" with only a few residents left.