Updated 16 January 2009
Grants Mineral Belt
The Grants Mineral Belt is the largest uranium province in the United States. Located in west-central New Mexico, the belt encompasses all of the significant uranium deposits in the state.
Grants Mineral Belt, along the south margin of the San Juan Basin, contains the Chuska, Gallup, Ambrosia Lake, and Laguna uranium mining districts. Uranium is largely contained in the Jurassic Jackpile, Poison Canyon, and Westwater Canyon sandstone members of the Morrison Formation, and in the underlying Todilto limestone.
Grants Mineral Belt, New Mexico
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The southern part of the Ambrosia Lake district immediately northeast of the town of Grants hosts substantial uranium deposits in both the Todilto Limestone and the Poison Canyon Sandstone. The bulk of mineralisation in northern Ambrosia Lake is in the underlying Westwater Canyon sandstone.
Most of the region is a semi-arid terrain of mesas and broad valleys. The uranium-producing localities range in elevation from about 1700m to about 2250m above sea level.
Todilto Limestone
More than 100 uranium deposits are known in the Todilto Formation in New Mexico, of which 42 have been mined.Most of these are in the Grants area, although numerous drill holes exceeding depths of 300m in the Ambrosia Lake is district encountered uranium minerals in the Todilto.
Exploration Strategy
Grants Ridge presents an opportunity to identify substantial tonnages of near-surface uranium ore in the Todilto, which has been under-explored compared to the overlying the more famous Morrison Formation.
Historic mining of the period 1950-1980s focused only on high grades, and was generally fairly small-scale due to the discontinuous nature of the higher grade lenses. Substantial areas of uranium at attractive grades are known to exist around these mines. There has been very little exploration in the region since the 1980s.
Uran intends to seek to define near-surface uranium deposits suitable for larger-scale bulk mining.
There is a significant amount of drilling data still available for the project, with substantial coverage in the Sections 4 & 9 area from both Anaconda’s and Homestake’s operations and from Homestake’s underground mine at F33. These will be located on the ground and form a basis for planning further drilling.
Current activity in the Grants district
Active uranium mining stopped in New Mexico in 1998, although Rio Algom recovered uranium dissolved in water from flooded underground workings at Ambrosia Lake until 2002. No uranium mining is currently taking place, although New Mexico has the second-largest known uranium reserves in the U.S.
 Drilling on the main
Faith ore trend, Todilto limestone, Grants area. (McLaughlin, 1963)
Note: in the 1960s the term “ore body” was only applied to grades of more than 0.2% in thicknesses of more than 5 feet (1.5m).
General Atomics subsidiary Rio Grande Resources is currently evaluating its Mt Taylor Mine for development by in-situ leaching. Uranium is present as coffinite in the Westwater Canyon member of the Morrison Formation at 3,000 feet (900m) below surface. The mine, which operated from 1986 to 1989, has a remaining resource estimated and published by its owner at more than 35,000 t U3O8.
Strathmore Minerals Corp. is currently applying for permits to mine its Church Rock and Roca Honda properties in the Grants mineral belt. They are yet to develop their Marquez deposit in spite of its large historical resource estimate.
 Nearby Resources and Production Statistics
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