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Uranium Energy Corp, Yellowcake in storage drum at UEC plant in New York, 2011, Flickr

Issue Brief

What is Yellowcake?

Yellowcake is the final material produced from uranium ore in the milling process. The material is a solid mixture of uranium oxides and can vary in coloring from yellow to dark green. It is generally more than 80% uranium. U.S. Nuclear Regulatory Commission, "Yellow Cake," June 30, 2020 [last updated], https://www.nrc.gov/reading-rm/basic-ref/glossary/yellowcake.html.Uranium recovery facilities that utilize in situ recovery methods produce a yellowish compound. The material is then transported to a uranium conversion facility where it is converted into enriched uranium in preparation for fabricating fuel for nuclear reactors.

By 1958 uranium had transformed Uravan, Colorado, Grants, New Mexico, and Jeffrey City, Wyoming, U.S. Nuclear Regulatory Commission, "Yellow Cake," June 30, 2020 [last updated], https://www.nrc.gov/reading-rm/basic-ref/glossary/yellowcake.html.into “yellowcake communities” or “yellowcake towns”—a reference to the way uranium oxide solids resemble yellow cake mix. These towns’ economies, landscape, and images were completely transformed by the federal government’s demand for uranium. Michael A. Amundson, Yellowcake Towns: Uranium Mining Communities in the American West (Boulder, CO: University Press of Colorado, 2002), https://www.jstor.org/stable/j.ctt2tv5vcFor example, by 1960, the town of Uravan included attributes largely uncommon for its size, such as a new pool, doctor, volunteer fire crew, library, gym, and movie theater. Because these towns were supplying raw material for the first atomic bombs and for nuclear plants, the mining materials were viewed in a very different context than other mining towns. Many uranium town residents showed a “pronuclear” culture: people built “uranium cafes” and staged “Miss Uranium” pageants. Up to 1957, the growing dependence on uranium led to unexpected growth, but as policies shifted and the government lost its complete control of the industry, progress and growth began to slow down, and eventually halted. What had been a booming part of Colorado’s overall economy went “bust” due to a combination of factors, including the U.S. government’s shift from domestic production to cheaper sources of uranium in the international market. Formerly a national supplier of uranium, Colorado state would face numerous mine closures and eventually almost no production of uranium.

Peter Hessler, "The Uranium Widows,” The New Yorker, September 6, 2010, https://www.newyorker.com/magazine/2010/09/13/the-uranium-widows.Several uranium towns in southwest Colorado currently advocate for new mining projects, to reverse the historical decline of the U.S. uranium industry that decimated local communities and livelihoods. Demands for the economic revival of domestic uranium production can appear contradictory due to concerns over the health consequences of uranium mining. Research dating back to the 1950s shows a connection between Bernard Conway, "Uranium Mining," Colorado Encyclopedia, accessed July 31, 2020, https://coloradoencyclopedia.org/article/uranium-mining.dangerous mining practices and cancer-related deaths in miners. Despite the growing evidence of health risks, many natives of mill towns still support new mining operations and accept a certain level of risk associated with mining practices. Families with a history of uranium mining are often proud of the way uranium miners confronted difficult conditions in order to provide financial support. Uranium mining is a crucial part of their identity and culture, and Peter Hessler, "The Uranium Widows,” The New Yorker, September 6, 2010, https://www.newyorker.com/magazine/2010/09/13/the-uranium-widows.it is not uncommon for members of these communities to have uranium ore in their houses as a keepsake.

Today these mining towns face challenges over the legacies and future of mining, and remain wary that regulatory efforts, environmentalists, and protesters of mining’s hazards threaten their way of life. Some communities have found ways of moving beyond unhealthy and unsustainable practices while respecting the culture of the miners. In the case of Uravan, unsafe levels of radiation forced community members to move elsewhere, leaving the abandoned townsite under the supervision of the nation’s Superfund cleanup program.


Amundson, Michael A. Yellowcake Towns: Uranium Mining Communities in the American West. Boulder, CO: University Press of Colorado, 2002.

Conway, Bernard. "Uranium Mining." Colorado Encyclopedia. Last updated June 1, 2020. Accessed July 31, 2020.

European Nuclear Society. "Yellow Cake." Accessed July 31, 2020.

Hessler, Peter. “The Uranium Widows.The New Yorker, September 6, 2010. Accessed March 22, 2021.

U.S. Nuclear Regulatory Commission. "Yellow Cake." June 30, 2020 [last updated]. Accessed July 31, 2020.

World Nuclear Association. "Nuclear Fuel Cycle Overview." May 2020 [last updated]. Accessed July 31, 2020.

"Yellowcake Explained." CBC News. July 22, 2008 [last updated]. Accessed July 31, 2020.

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