Table T5. Instrumental conditions for XRF major and trace element standard measurements.

Element	Line	Crystal	Detector	Collimator	Peak angle (°2)	Background offset (°2)	Total peak (s)	Count time background (s)	Analytical error (SD%)	Detection limit (%)
Major
SiO2	SiKa1,2r	PET	FPC	Medium	109.21	NB	60	NB	0.20	0.030
TiO2	TiKa1,2r	LIF200	FPC	Fine	86.14	NB	100	NB	0.56	0.009
Al2O3	AlKa1,2r	PET	FPC	Medium	145.12	NB	100	NB	0.55	0.041
Fe2O3	FeKa1,2r	LIF200	FPC	Fine	57.52	NB	90	NB	0.42	0.007
MnO	MnKa1,2r	LIF200	FPC	Fine	62.97	NB	200	NB	2.12	0.006
MgO	MgKa1,2	TLAP	FPC	Medium	45.17	-0.80	200	200	0.40	0.050
CaO	CaKa1,2r	LIF200	FPC	Medium	113.09	NB	120	NB	0.25	0.003
Na2O	NaKa1,2	TLAP	FPC	Medium	55.10	1.20	210	210	1.21	0.100
K2O	KKa1,2r	LIF200	FPC	Medium	136.69	NB	175	NB	0.89	0.001
P2O5	PKa1,2s	GE111	FPC	Medium	141.04	NB	175	NB	1.56	0.003
Trace
Nb	Ka	LIF200	Scint	Fine	21.40	+0.35	100	100	2.0	1
Zr	Ka	LIF200	Scint	Fine	22.55	-0.35	100	100	0.7	1
Y	Ka	LIF200	Scint	Fine	23.80	-0.40	100	100	2.7	1
Sr	Ka	LIF200	Scint	Fine	25.15	-0.40	100	100	1.1	1
Rb	Ka	LIF200	Scint	Fine	26.62	-0.60	100	100	8.1	1
Zn	Ka	LIF200	Scint	Fine	41.81	-0.55	100	100	1.8	2
Cu	Ka	LIF200	Scint	Fine	45.03	-0.40	100	100	1.3	2
Ni	Ka	LIF200	Scint	Fine	48.67	-0.40	100	100	1.2	2
Cr	Ka	LIF200	FPC	Fine	69.35	-0.50	100	100	0.8	3
V	Ka	LIF220	FPC	Fine	123.06	-0.50	100	100	1.1	4
Ce	La	LIF220	FPC	Medium	128.16	-1.50	100	100	5.6	10
Ba	Kb	LIF220	FPC	Medium	128.78	-1.50	100	100	5.8	15

Notes: SD = standard deviation; NB = no background correction. The standard reference material BHVO-1 was used to quantify analytical error.