Samples	δ66Zn	2se	δ 68Zn	2se	na
replicate 1	0.34	0.01	0.68	0.04	4
replicate 2	0.34	0.01	0.68	0.01	3
replicate 3	0.34	0.02	0.67	0.02	4
replicate 4	0.36	0.06	0.7	0.09	4
replicate 5	0.31	0.02	0.65	0.06	4
replicate 6	0.33	0.01	0.68	0.02	3
replicate 7	0.32	0.06	0.63	0.1	6
Average	0.33	0.03	0.67	0.05	7
2SD	0.04		0.05
a n=number of repeat measurement by MC-ICP-MS