DESCRIPTION BL-5 is a low-grade concentrate from Beaverlodge, Saskatchewan. The major mineralogical components are, in decreasing order of abundance: plagioclase feldspars, hematite, quartz, calcite and dolomite, chlorite and muscovite; uraninite is the main uranium-bearing mineral. The concentrate was dried at 100°C, dry-ground to minus 74 µm, blended, sampled systematically for analysis by X-ray fluorescence and chemical methods to demonstrate homogeneity sufficient for use as a compositional reference material for uranium and bottled in 100-g units. Evidence is available that BL-5 is in secular equilibrium. CERTIFICATION The consensus value for uranium is the unweighted mean of 337 accepted analytical determinations by 24 laboratories. Methods included titrimetry, colorimetry, fluorimetry, x-ray fluorescence, neutron activation analysis, radiochemistry and isotope dilution. LEGAL NOTICE The Canadian Certified Reference Materials Project has prepared this reference material and statistically evaluated the analytical data of the inter-laboratory certification program to the best of its ability. The Purchaser by receipt hereof releases and indemnifies the Canadian Certified Reference Materials Project from and against all liability and costs arising out of the use of this material and information. REFERENCE The preparation and certification procedures used for BL-5 are given in CANMET Reports 79-4 "Uranium Ore BL-5 – a Certified Reference Ore", 83-9E "Radium-226 in Certified Uranium References Ores DL-1a, BL-4a, DH-1a and BL-5" and 84-11E "Lead-210 in Certified Uranium Reference Ores DL-1a, BL-4a, DH-1a and BL-5" which are available free of charge on request to: |