Element | Certified Concentration | Observed Concentration (n = 2) | Rel. Error (%) | Recovery (%) |
Cu | 25.1 ± 3.8 | 25.9 ± 2.4 | 3.2 | +103.2 |
Cr | 71.0 ± 11 | 69.8 ± 3.7 | 1.7 | −98.3 |
Mn | 513 ± 25 | 496.1 ± 18 | 3.3 | −96.7 |
Zn | 191 ± 17 | 202.2 ± 19 | 5.9 | +105.9 |