Table 3.

Pearson’s linear correlation coefficients (r) between elements

	Al (I)	Ba (I)	Ca (I)	K (I)	Mg (I)	Na (I)	Ti (I)	Co (II)	Cr (II)	Cu (II)	Fe (II)	Mn (II)	Ni (II)	Pb (II)	V (II)	Zn (II)	P (III)	S (III)
Al (I)	–	0.96*	0.99*	0.99*	0.96*	0.99*	0.83	− 0.92*	− 0.96*	− 0.70	− 0.91*	− 0.81	− 0.94*	− 0.99*	− 0.97*	− 0.96*	− 0.40	0.52
Ba (I)		–	0.92*	0.98*	0.84	0.96*	0.87	− 0.97*	− 0.98*	− 0.85	− 0.94*	− 0.90*	− 0.96*	− 0.97*	− 0.97*	− 0.99*	− 0.60	0.36
Ca (I)			–	0.97*	0.98*	0.99*	0.78	− 0.89*	− 0.94*	− 0.63	− 0.89*	− 0.76	− 0.92*	− 0.98*	− 0.95*	− 0.92*	0.55	− 0.18
K (I)				–	0.92*	0.99*	0.82	− 0.97*	− 0.99*	− 0.78	− 0.96*	− 0.89*	− 0.98*	− 0.99*	− 0.99*	− 0.99*	− 0.52	0.37
Mg (I)					–	0.96*	0.66	− 0.84	− 0.88*	− 0.56	− 0.81	− 0.70	− 0.88*	− 0.94*	− 0.91*	− 0.86	− 0.26	0.55
Na (I)						–	0.80	− 0.94*	− 0.97*	− 0.73	− 0.92*	− 0.84	− 0.96*	− 0.99*	− 0.98*	− 0.97*	− 0.44	0.47
Ti (I)							–	− 0.73	− 0.78	− 0.59	− 0.77	− 0.62	− 0.72	− 0.80	− 0.76	− 0.83	− 0.28	0.61
Co (II)								–	0.99*	0.88*	0.96*	0.97*	0.99*	0.95*	0.98*	0.98*	0.69	− 0.16
Cr (II)									–	0.84	0.97*	0.94*	0.99*	0.98*	0.99*	0.99*	0.61	− 0.27
Cu (II)										–	0.76	0.93*	0.85	0.78	0.80	0.87	0.92*	0.06
Fe (II)											–	0.92*	0.96*	0.92*	0.97*	0.95*	0.55	− 0.18
Mn (II)												–	0.95*	0.86	0.92*	0.93*	0.82	0.06
Ni (II)													–	0.97*	0.99*	0.98*	0.64	− 0.21
Pb (II)														–	0.98*	0.98*	0.50	− 0.44
V (II)															–	0.98*	0.56	− 0.30
Zn (II)																–	0.63	− 0.31
P (III)																	–	0.42
S (III)																		–

Positive linear correlation coefficients between elements suggest common origins (Bastami et al. 2014, 2017)

^*p < 0.05. I, II, and III indicate the different groups identified by PCA