Large-scale uranium exploration programs and industrial mine development require rapid and accurate analytical determinations of uranium and associated elements, at concentration levels ranging from a few parts-per-million to the per-cent range. The analytical requirements for associated suites of elements vary with application, but quality control and production practices in U.S. uranium mines and mills commonly require determinations of calcium, iron, copper, molybdenum, and vanadium, in addition to uranium. Previous work has demonstrated the capabilities of wavelength-dispersive x-ray spectrometric methods for many exploration applications. The purpose of this investigation is to assess the accuracy of x-ray determinations of uranium at ore-grade levels, utilizing both wavelength-dispersive and energy-dispersive spectrometers, and to discuss the acquistion of multi-element data.