Hydrogen and Oxygen Stable Isotope Ratios of Dolomite-Related Nephrite: Relevance for its Geographic Origin and Geological Significance

GEMS & GEMOLOGY SUMMER 2020 Nephrite is a near-monomineralic rock composed of tremolite-actinolite, Ca2(Mg,Fe)5Si8O22(OH)2. It occurs worldwide (figure 1) and is classified as dolomite-related or serpentine-related according to the different parent rocks and ore-hosting rocks, and both types form by metasomatism (Yui et al., 1988; Tang et al., 1994; Yang and Abduriyim, 1994; Harlow and Sorensen, 2005; Burtseva et al., 2015). The large and well-known dolomite-related nephrite deposits are distributed in the Xinjiang Uyghur Autonomous Region (hereafter abbreviated as Xinjiang) of China, Qinghai Province of China, Siberia in Russia, and Chuncheon in South Korea (figure 1). Data from smaller-scale deposits such as Val Malenco in Italy and Złoty Stok in Poland are also used in this study (figure 1). The rest of the data were collected from nephrites produced at multiple small-scale sources in China: Xiuyan, Tanghe, Dahua, and Luodian (figure 2). With nephrite jade, a premium is placed on geographic origin since the gem’s cultural significance differs by location. It is possible to have an opinion