Between-bottle homogeneity test of new certified reference materials employing wavelength dispersive X-ray fluorescence spectrometry

Table 4 Descriptive statistics of elements contents (weight%) in KACST404 CRM

Element	Average	SD	RSD%	RAD%	Skewness	Kurtosis
Al	1.780	0.0082	0.46	0.32	0.00	− 1.20
Ca	24.76	0.1134	0.46	0.38	0.24	− 1.23
Cl	0.368	0.0020	0.55	0.48	0.13	− 1.96
Cr	0.034	0.0006	1.86	1.52	0.08	− 1.77
Cu	0.021	0.0010	4.78	4.27	− 0.45	− 2.32
Fe	2.467	0.0325	1.32	1.17	− 0.25	− 2.49
K	0.604	0.0008	0.13	0.11	1.11	0.27
Mg	0.865	0.0082	0.94	0.82	− 0.58	− 1.77
Mn	0.036	0.0002	0.60	0.48	− 1.11	0.86
Na	0.358	0.0012	0.34	0.27	− 1.15	− 0.06
Ni	0.027	0.0031	11.6	10.1	− 0.23	− 2.24
P	0.079	0.0002	0.22	0.19	0.38	− 2.11
Pb	0.015	0.0001	0.59	0.48	0.35	− 1.82
Rb	0.004	0.0003	8.10	6.29	− 0.26	− 0.89
S	0.612	0.0068	1.10	0.89	− 0.44	− 1.50
Si	8.950	0.0764	0.85	0.67	0.86	− 0.87
Sr	0.042	0.0003	0.65	0.55	0.00	− 2.31
Ti	0.331	0.0012	0.35	0.26	0.91	− 0.15
Zn	0.037	0.0016	4.29	3.41	− 0.51	− 0.90
Zr	0.082	0.0008	0.92	0.76	0.25	− 1.42

SD standard deviation, RSD relative standard deviation, RAD relative average deviation

ISSN: 2661-801X