Product tags
Producing Laboratory: TERC
Thorium Ore

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.

AnalyteValueUnit95% C.I.NR/I/C
232Th3250?Bq/kg3160 - 3340155R
235U3.6?Bq/kg3.3 - 3.9145R
238U78?Bq/kg72 - 84145R
40K6.3?Bq/kg3.1 - 9.545I
K200mg/kg100 - 30045I
Th800mg/kg784 - 816155R
U6.3mg/kg5.9 - 6.7145R
(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).