School of Engineering and Science - Jacobs University

10 2 JDo-1 reference values
10 1
IF-G reference values
IQL HCl (n=21)
method blank HCl (n=19)
10 0
10 -1
mg/kg
10 -2
10 -3
10 -4
10 -5
10 -6
10 -7
10 2 Sc Ti Co Ni Rb Sr Y Zr Nb Mo Cs Ba La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf Ta W Pb Th U
10 1
0.5 M HCl
IQL HNO3 (n=3)
method blank HNO3 (n=3)
10 0
10 -1
mg/kg
10 -2
10 -3
10 -4
10 -5
10 -6
10 -7
0.5 M HNO3
Sc Ti Co Ni Rb Sr Y Zr Nb Mo Cs Ba La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf Ta W Pb Th U
Figure 4. Long term average instrument quantification limits in mg/kg for solid samples (i.e.,
accounting for dilution factors) as determined from acid blanks, and average method blanks. Data for
acid blank IQLs are also presented in Table 2. The top figure corresponds to a 0.5 M HCl acid matrix,
and includes average method blanks for the HF-HClO 4 pressure decomposition method as well as
reference data for the iron-formation IF-G, which represents a rock type that contains very low trace
metal contents typically dissolved using the HF-HClO 4 method. The bottom figure corresponds to a 0.5
M HNO 3 acid matrix and the carbonate decomposition method, and includes reference data for the
dolomite JDo-1, which represents a very low trace metal content rock typically dissolved using HNO 3 .
Regardless of decomposition method, the method blanks are at least 1 order of magnitude lower than
IQLs for all elements, and generally 3-6 orders of magnitude lower than concentrations observed in the
very trace metal-poor rocks typically analyzed. Method blanks and IQLs are significantly lower in 0.5
M HNO 3 . Note that some elements are likely to be unquantifiable in many trace metal-poor rock
samples due to concentrations close to or below the IQL (e.g., Sc, Nb, Ta).
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