IAEA-RGU-1 , Uranium Ore

Inorganic , Ores

Both, IAEA-RGU-1 and IAEA-RGTh-1 reference materials were prepared on behalf of the International Atomic Energy Agency by the Canada Centre for Mineral and Energy Technology by dilution of a uranium ore BL-5 (7.09% U) and a thorium ore OKA-2 (2.89% Th, 219 μg U/g) with floated silica powder of similar grain size distribution, respectively. No evidence for between-bottles inhomogeneity was detected after mixing and bottling. BL-5 has been certified for uranium, 226Ra and 210Pb confirming that it is in radioactive equilibrium. The agreement between radiometric and chemical measurements of thorium and uranium in OKA-2 shows both series to be in radioactive equilibrium.

Analyte Value Unit 95% C.I. N R/I/C
232Th < 4? Bq/kg - None I
235U 228? Bq/kg 226 - 230 None R
238U 4940? Bq/kg 4910 - 4970 None R
40K < 0.63? Bq/kg - None I
K < 20 mg/kg - None I
Th < 1 mg/kg - None I
U 400 mg/kg 398 - 402 None R
(Value) Concentration calculated as a mean of the accepted laboratory means 
(N) Number of accepted laboratory means which are used to calculate the recommended or 
information values and their respective confidence intervals
(R/I/C) Classification assigned to the property value for analyte (Recommended/Information/Certified)
(?) Natural radionuclide activity concentrations derived from the elemental concentrations on basis of isotopic abundance and half-life data

The values listed above were established on the basis of a gravimetric dilution of materials with known uranium, thorium and potassium composition. The details concerning the criteria for qualification as a recommended or information value can be found in the respective report (attached).

Help and Service
Copyright © 2009 International Atomic Energy Agency, P.O. Box 100, Wagramer Strasse 5, A-1400 Vienna, Austria