School of Engineering and Science - Jacobs University

30
25
JDo-1 (n=3)
sample precision HNO 3
36.3% method precision HNO 3
59.3%
method precision HF-HClO 4
20
%RSD
15
10
5
0
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 9. Average sample and method precision for the HNO 3 carbonate decomposition of the JDo-1
dolomite CRM (for run precision see Fig. 7). Method precision for the carbonate decomposition is
better than 5% for 25 of the 32 elements analyzed, and poorer precision is generally restricted to
elements typically hosted in refractory silicate minerals (Rb, Cs, Hf).
determined for the carbonate decomposition is quite similar to that observed for the
HF-HClO 4 decomposition method, though the HF-HClO 4 decomposition results in
significantly better precision for elements typically hosted by silicate minerals (e.g.,
Rb, Zr, Cs, Hf), due to the complete dissolution of refractory Si-bearing phases.
6. Analytical recovery
The relative precision for most elements analyzed is quite good, but this
provides no information regarding potential loss of these elements as a consequence
of the sample decomposition or ICPMS measurement. Some elements can exist as a
volatile chemical species at some point during the decomposition process, and
therefore may exhibit non-conservative behavior during sample preparation. The best
example of this is Si, which is converted to volatile SiF 4 during HF dissolution of
silicate minerals, and is consequently lost from the sample during evaporation of HF
early in the HF-HClO 4 decomposition method. The ability of the sample treatment
and ICPMS measurements described here to conserve the elements of interest
throughout the decomposition and analytical procedure is termed analytical recovery.
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