The historical significance of the Powder River basin uranium deposits is twofold: (1) the first economical Tertiary uranium deposits in Wyoming were discovered in the Pumpkin Buttes area of the Powder River basin, and (2) the surface to near-surface exposure of these ores provided the basic information needed to develop exploration models for prospecting in similar Tertiary basins in Wyoming.

The first commercial production of uranium within the Powder River basin began in 1953 and continued until 1965. Most of this early production came from mining operations concentrated along high-grade (as high as 15% uranium and nearly 3% vanadium) concretionary deposits limited in size and extent. Because of the size of these deposits, only small tonnages were realized, and as many as 55 separate mining operations were reported within the first 15 years. A second uranium boom began in the early 1970s with the discovery of several low-grade disseminated roll fronts near Pumpkin Buttes and in the southern Powder River basin. Production from the low-grade disseminated deposits has totaled nearly 180 times more ore tonnage than that produced from the high-grade concretionary deposits. To al ore production within the basin amounts to more than 5 million tons of ore, and increased production is expected over the next several years.

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