Gemological And Mineralogical Study Of Nephrite In South Korea

There are quite a few kinds of （different provenance） nephrite jades in domestic jades market, the nephrite’s price of different provenance is very different, so distinguish the nephrite from different provenance is especially important and pressing.Now, there are a lot of jade products made of Korean nephrite in domestic market. But so far, the research of the Korean nephrite is also virtually nonexistent. This paper is designed to the chemical composition and minerals component of South Korean nephrite for the further study and analysis, in order to find out the differences of the nephrite of different provenances, with the purpose of distinguishing the provenances. This article has researched the basic physical properties, basic element content, structural characteristics and causes characteristics by microscopic observation, Scanning Electron microscope testing, Electronic probe quality testing, infrared spectroscopy （IRS） and ICP testing. The research shows the main constituent parts of the jades is tremolite, level in more than 95 %. Minerals are very small particles. Microaphanitics is the main part of the nephrite and the metasomaric texture illusion exists widely. By Scanning Electron microscope testing, the main part of Korean nephrite is schistose, threadiness, LA-ICP-MS Test results reflects: Light rare earth elements are enriched; heavy rare earth elements are poor. Eu is negative anomaly seen from the REE images.Contrast the basic properties with different places of provenances, it is clearly Korean nephrite’s density and hardness is lower than those of other kinds of nephrite. Compare with HeTian nephrite, Korean nephrite is good at transparency and particles are relatively heavy. The research shows the main constituent parts of the nephrite of HeTian, QingHai, Russia, Jiangsu etc, is tremolite by SMART APEX-CCD X and infrared spectroscopy testing, but finding that the impurities minerals to the larger are quite different through the further study. The impurity minerals of Korean nephrite are calcite, epidote, limonite, etc. Electronic probe quality testing shows that Korean nephrite and nephrite of Baikal Lake, Russia has higher SiO₂ content, and then comes to QingHai nephrite, HeTian nephrite Contents with a minimum. CaO of QingHai nephrite is enriched, while FeO, Al₂O₃, K2O is poor. CaO, FeO, Al₂O₃, K2Oof Korean nephrite is moderate,close to Theory contents. Compared with the results of LA-ICP-MS testing, it shows that Korean nephrite Contain more Ti,Zn, while less Cu,Mo,Hf,Ta.