Uranium content and leachable fraction of fluorspars

E. R. Landa; T.B. Councell

doi:10.1097/00004032-200009000-00009

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Uranium content and leachable fraction of fluorspars

E. R. Landa·T.B. Councell

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Abstract

Much attention in the radiological health community has recently focused on the management and regulation of naturally occurring radioactive materials. Although uranium-bearing minerals are present in a variety of fluorspar deposits, their potential consideration as naturally occurring radioactive materials has received only limited recognition. The uranium content of 28 samples of acid- and cryolite-grade (> 97% CaF2) fluorspar from the National Defense Stockpile was found to range from 120 to 24,200 μg kg−1, with a mean of 2,145 μg kg−1. As a point of comparison, the average concentration of uranium in the upper crust of the earth is about 2,500 μg kg−1. Leachability of this uranium was assessed by means of the Toxicity Characteristic Leaching Procedure (TCLP). The TCLP extractable fraction ranged from 1 to 98%, with a mean of 24% of the total uranium. The typically low concentrations of uranium seen in these materials probably reflects the removal of uranium-bearing mineral phases during the beneficiation of the crude fluorspar ore to achieve industrial specifications. Future NORM studies should examine crude fluorspar ores and flotation tailings.

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E. R. Landa, T.B. Councell. 2000. Uranium content and leachable fraction of fluorspars. https://doi.org/10.1097/00004032-200009000-00009

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