Trace elements commonly associated with sandstone-type uranium deposits include V, Mo, Se, and some As, Cu, and Pb. Because V, Mo, and Se are usually included in separate phases, all uranium-free, their use as pathfinders for uranium deposits is straightforward but often hindered by high background from the non-ore country rocks or other non-ore phases. Data for numerous

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other trace elements have been gathered, but many are of limited use owing to low precision and accuracy of analytical methods or failure to separate authigenic from detrital minerals. It is essential to separate the < 2-µ fraction from barren oxidized, barren reduced, and mineralized rocks from sandstone-type uranium deposits to address quantitatively the problems of paragenesis. Elements now considered important which are commonly enriched in the authigenic fraction include the rare earth elements (REE), Sb, Ta, Ba, Cs, Rb, Sr, Co, Ni, and others. The chalcophile elements allow definition and tracing of redox fronts, Rb/Sr systematics, and Rb/Cs ratio aspects of primary versus remobilized mineralization. Tantalum and antimony for primary reduced from re-reduced ground and th REE distribution patterns for rocks penetrated by uraniferous solutions are different from those of barren rocks.

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