Two spodumene samples for helium isotope standard were prepared. According to the preparation criterion on first grade national standard materials, homogeneity tests of helium contents and isotope compositions of two samples were carried out using the heat melt method. The homogeneity tests and certification analysis show that 4He contents and 3He/4He ratios of two reference material samples are homogeneous. Afterward two standard samples were distributed to four laboratories for cooperative fixed values. All data of various laboratories submit to normal distribution and not abnormity values. The average values of each laboratory are recommended as values of two spodumene samples for helium isotope standard.
Journal of Chinese Mass Spectrometry Society