Radioactive ores DH-1, DL-1, BL-1, BL-2, BL-3 and BL-4 - certified reference materials

The preparation and characterization of a set of six ores of the naturally radioactive elements, for use as certified reference materials in chemical and radiometric analysis, is described. The set consists of two series representing Canada's original uranium-producing areas--Elliot Lake in Ontario and Beaverlodge in Saskatchewan. The Elliot Lake series comprises two samples, one of ore and the other of waste-grade material, both of whichcontain uranium and thorium. The second series consists of essentially thorium-free material from Beaverlodge, covering the rangeof 0.02% to The former is intended as a reference material for chemical determination of uranium and thorium, while the latter may also be employed in calibrating and verifying radiometric surveying and assaying equipment. In addition to their uranium and thorium contents, supplementary information as to mineralogical composition, state of radioactive equilibrium, and composition with respect to most common and many trace elements of significance in ore processing is given. The recommended values for uranium in DH-1, DL-1, BL-1, BL-2, BL-3, and BL-4 aie respectively: 0.177%, 0.0041%, 0.022%, 0.453%, 1.02% and 0.173%; recommended values for thorium in DH-1, DL-1 and BL-1 are respectively: 0.104%, 83 ppm (83 lig/g) and 15 ppm (15 pg/g).