Table T1. Accuracy of standard reference material NIST-1c in shore-based (flux and microwave-assisted digested) measurements.
Element
Published
value
Measured
value (N = 6)
Major element oxide (wt%):
SiO2 6.84 ± 0.08 6.78 ± 0.24
Al2O3 1.30 ± 0.03 1.28 ± 0.02
TiO2 0.070 ± 0.010 0.069 ± 0.002
Fe2O3 0.55 ± 0.03 0.56 ± 0.02
MnO 0.025 ± 0.005 0.021 ± 0.001
CaO 50.3 ± 0.3 50.4 ± 1.0
MgO 0.42 ± 0.04 0.39 ± 0.01
Na2O 0.020 ± 0.010 0.020 ± 0.001
K2O 0.28 ± 0.01 0.29 ± 0.01
P2O5 0.04 ± 0.01 0.038 ± 0.001
Trace element (ppm):
Ba NR 56.3 ± 1.5
Sr 254 ± 42 257 ± 8
Cr NR 11.7 ± 0.3
Ni NR 8.91 ± 0.45
Sc NR 1.47 ± 0.04
V NR 10.4 ± 0.4
Zr NR 35.1 ± 1.4

Notes: Error reported as 1. NR = not reported.