Determination of manganese in certified reference materials.

Sample	Certified reference materials (composition, %)	Manganese (%)
		In CRM sample	Found (n = 5)	RSDa
1	BCS-CRM 163, unalloyed steel (C = 1.2, Mn = 0.472, Ni = 0.608, Si = 0.18, Cu = 0.05, Cr = 0.03)	0.472	0.47	1.5
2	BAS-CRM-10g, high-speed brass (Cu = 60.8, Fe = 1.56, Pb = 0.23, Ni = 0.16, Sn = 0.21, Al = 3.34, Zn = 32.0, Mn = 1.36)	1.36	1.35	1.2
3	BCS-CRM-238, unalloyed steel (C = 0.2, Si = 0.06, S = 0.05, Mn = 0.51, Ni = 0.06, Cr = 0.06 and Cu = 0.05)	0.51	0.50	2.0
4	BAS-CRM-1d, mild steel (C = 0.19, Si = 0.06, S = 0.04, Mn = 0.52, P = 0.04)	0.52	0.518	1.8
5	BAS-CRM-33b, alloy cast iron (Mn = 0.64, Cr = 0.61, Mo = 0.04, Ni = 2.24)	0.64	0.625	1.6
6	CRM-BCR-397, human hair	11.2 ± 0.3b	11.15 ± 0.5	1.0
7	NIST-SRM-1646, estuarian sediment	234.5c	232.0	1.5

^aThe measure of precision is the relative standard deviation (RSD).

^bValues in μg g⁻¹.

^cValues in mg kg⁻¹.