jade, nephrite, China, Korea, Russia, gems

Provenance studies on nephrite jade are of gemological as well as archeological importance. Origin determination is difficult to achieve relying solely on typical gemological properties and observations. In this study, the authors present a new statistical analysis method, based on linear discriminant analysis (LDA) and trace-element data from laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS), to achieve significantly improved origin determination (an average of 94.4% accuracy) for eight major dolomite-related nephrite deposits in eastern Asia. As the principle is to compare one location to the rest in one round and continue such binary comparison until all possible localities are tested, the method is referred to as iterative-binary LDA (IB-LDA). Combined with trace-element composition data from LA-ICP-MS, it could prove to be a useful technique for the geographic origin determination of other gemstones.