Element | Certified Concentration (MAD) | Observed Concentration (n = 3) | Rel. Error (%) | Recovery (%) |
Cu | 6.05 (3.50) (n = 6) | 7.73 ± 0.98 | 27.8 | +127.8 |
Cr | 2.35 (1.65) (n = 4) | 2.81 ± 0.80 | 19.6 | +119.6 |
Mn | 20.0 (4.00) (n = 5) | 20.35 ± 0.86 | 1.8 | +101.8 |
Zn | 18.5 (2.80) (n = 6) | 17.10 ± 1.33 | 7.6 | −92.4 |