Reevaluation of the homogeneity of REE, TH and U in geochemical reference zircon 61.308B

In a previous study of the reference sample zircon 61.308B, it has been suggested that either the sample is heterogeneous or inter-method comparisons introduce analytical dispersions. New determinations by LA-ICP-MS show relative standard deviation in the order of 20% for Heavy Rare Earth Elements (HREE). This is four times the variation attributable to analytical method. A possible explanation is that HREE concentration variations in geochemical reference zircon were created by crystal fractionation or oscillatory variation in the host magma. This confirms that zircon 61.308B is heterogeneous for trace elements.