Abstract:The present paper introduces three kinds of traditional jade including Hetian jade and plentiful culture of jade in various dynasties. Hetian jade has very important position in history, it is considered as emperor jade, its special characteristics provide favorable impression for people.

Abstract:Exploration and utilization of Hetian jade has very long history, it acts very important role in ancient jadeware of China. Hetian jade is main material making jadeware in ancient China from later period of the New Stone Age to Qing Dynasty; Hetian jade has unique white color like sheep fat, while nephrite in other region hasn't this color. Jadeware made by Hetian jade is main record of traditional jade culture, it can not be reproduced.

Abstract:The name of Hetian jade has been spread in China for ages, it has long history. Hetian jade was a main material for producing jade objects in ancient palace, it provided plentiful jade culture and opened up "the way of jade". Hetian jade belongs to tremolite jade, its mineral deposit was derived from contact metasomatism of mid-acid intrusive rock and dolomite marble. The jade has typical significance internationally. The name of nephrite has been used for just about one hundred years, it still has some problems. The authors suggest to replace the name of nephrite with tremolite jade.

Abstract:Manasi green jade belongs to tremolite jade, it is a kind of ancient jade. The jade can be found in placer and primary deposit, it was exploited in Qing Dynasty. The primary deposit was serpentinized pyroxene peridotite derived from ultramafic rocks, it was located in contact belt of the rock body and country rock (volcanic rock or pyroclasts), and formed by matasomatism. The jade is called green jade since its colour is green.

Abstract:Study on Hetian jade from Hetian County, Xinjiang has been carried out by means of electron microprobe, Xray dIffraction, scanning electron microscope, etc.. The results show that the major mineral composition of Hetian jade is tremolite, and the major texture is felty texture. The genesis of Hetian jade, the significance for exploring deposits and archaeology are also discussed in this paper.

Abstract:Hetian jade, also called tremolite jade, is one kind of nephrite, it is aggregation of tremolite mineral. White jade, grey\|white jade and grey jade are major species of Hetian jade. According to electron microprobe analysis, the major species are mainly composed of tremolite, in which the main chemical components are SiO2、MgO and CaO, with minor components of Al2O3、FeO、TiO2and MnO, some impurity minerals are found in Hetian jade. The color of jade is mainly related to the content of Fe2+、Ti4+ and Mn2+. Macroscopically, Hetian jade has compact massive structure, under the scanning electron microscope, felty texture, interlocking micro\|texture and granular micro\|texture can be observed.

Abstract:The mineral compositions of Hetain jade,Manasi green jade and Xiuyan old jade have been investigated by means of electron microprobe.Based on the analyses, it can be determined that the major mineral composition of Hetain jade and Manasi green jade is tremolite and actinolite respectively, whereas Xiuyan old jade is composed of both tremolite and actinolite.The locality feature of Hetain jade, Manasi green jade and Xiuyan old jade have been discussed.

Abstract:The chemical composition, mineral component and structure type of Hetian jade in Xinjiang and the nephrite from Baikal Lake region in Russia are studied and compared. From the view of petrology, their distinction and similarity are summarized systematically. Their main compositions and essential minerals are similar, the main structure and appearances are different. The work are important for development and utlization of Hetian jade and the nephrite from Baikal Lake area in Russia.

Abstract:Hetian jade is a famous nephrite, it is also called Chinese jade. Its main mineral components are tremolite and actinolite. Different kinds of Hetian jade have different colors and qualities although they are composed of similar chemical and mineral components. Scanning electron microscope (SEM) and spectrometry are used to observe the micro-textures and to analyse the composition of these Hetian jades. It is concluded that the high-|quality Hetian jade, such as mutton-fat jade, white jade, is mainly composed of tremolite with good crystal form and interlocking micro\|texture, the grain size is less than 3μm; the spectrometry analysis shows that this kind of jade contains silicon, calcium and magnesium without iron and aluminum. The grain size of green Hetian jade is 3~10μm, it includes Al or Fe ion; the green color will be darker as content of Fe ion increases; the main mineral composition is actinolite instead of tremolite. The yellow Hetian jade with typical sucrosic micro-texture is due to anomalous increase of calcium.

Abstract:Nephrite is used to be considered as aphanitic mineral aggregate which belongs to Fe-poor and Mg-rich member of actinolite-tremolite series. Usually, the mineral names (tremolite and actinolite) are distinguished on the basis of Mg/(Mg+Fe2+) ratio( 0.9 to be considered as the boundary). 17 samples of Hetian jade, Manasi green jade and Xiuyan old jade which come from Xinjiang, Liaoning and Qinghai have been investigated by means of XRD. The results show that all the samples are almost totally composed of tremolite, very few impurity can be found. No distinct relationship between peak positions and FeO contents can be determined. The diffusion of the peak shape probably indicates the variaton of crystallinity and grain size of the mineral composition.

Abstract:IR spectra of 17 nephrite samples are obtained in this study. The M—OH stretching vibration bands show that the M1 and M3 sites are not only occupied by Mg2+and Fe2+, but also by Fe3+. This information might be useful to understanding the variety of nephrite’s color.

Abstract:This article systematically presents Xiuyan nephrite in Liaoning Province. It involves modes of occurrence, colours, mineral association, main chemical compositions, trace elements and rare earth elements, textural and structural types and physical properties. The source of minerogenic material and ore\|forming process are also comprehensively analysed.

Abstract:The white jade found in the past and the new grey-white jade, grey jade and green jade found in Liyang County, Jiangsu Province are studied by means of electron microprobe, X-ray diffraction, infrared spectrum, scanning electron microscope, etc.. The results show that the major mineral composition of Liyang tremolite jade is tremolite, not Na-tremolite as reported previously, the content of Na is normal. Based on study of the texture and structure, its major texture is almost same as that of Hetian jade, it proves that Liyang tremolite jade is also a typical tremolite jade. The genesis of the jade, the significance for exploring deposits and archaeology are also discussed in this paper.

Abstract:Meiling jade (a natural nephrite), derived from Xiaomeiling region in Liyang, Jiangsu Province, occurs in the outer contact zone between granite and marble. Besides field geological investigation, the methods of microscope and SEM (scanning electron microscope) observation, X-ray diffraction, electron microprobe analyses and determination of physical qualities are adopted for the study. The results show that the main mineral constituent is tremolite with nematoblastic texture, and a little magnetite and clay mineral. The main chemical components of tremolite are SiO2, MgO and CaO, the minor components are Na2O and P2O5, the contents of these components are higher than those in Hetian jade. Colors of Meiling jade are mostly white, grey-white and grey, the colors become darker as the content of Fe2+ increases. The jade is semitransparent or opaque, with vitreous luster, the average density is 2.99 g/cm3, the hardness is 5~6, and the refraction index is 1.61. Due to special texture, Meiling jade with large pieces and few cracks shows a good technological processing property.

Abstract:Meiling jade belongs to tremolite jade series, which can be classified as white jade, grey-white jade, and grey jade. The mineralogical and metallogenic features of Meiling jade have been studied on the bases of field work, microscopic observation , chemical and spectrum analyses. The results show that the mineral compositions of white jade and grey jade are mainly tremolite and Na-enriched tremolite respectively. It can be deduced that white jade was formed under the condition of contact metasomatism, whereas grey jade was the injected mass of “jade liquid” under the condition of low pressure and high temperature, formed later than white jade.

Abstract:Hetian jade is one of the most important tremolite jade resources in the world, and Hetian is the most important jade locality in China. A study on oxygen and silicon isotope of the nephrite ore deposits has been stated in this paper. The analytical results show that the δ18O and δ30Si values of the nephrite ore deposit are distributed in a narrow range, which are all lower than the values of the host rocks. It is suggested that the nephrite ore deposits in Hetian and Xiuyan may be the magmatic hydrothermal replacement deposit, and the nephrite deposit of Manasi green jade may be the metamorphic ore deposit.

Abstract:The ore-forming solution and the origin of silicon in Xiuyan nephrite were studied by means of H-, O-, Si-and S-isotope analyses. TheδD values of Xiuyan nephrite change narrowly from-70‰ to-76‰, while theδ18O values change from 8.1‰ to 13.3‰. The study shows that the compositions of hydrogen and oxygen isotopes in the ore-forming solution of Xiuyan nephrite lie in metamorphic water region, therefore Xiuyan nephrite was formed in metamorphic solution. The δ30Si values of Xiuyan nephrite range from-0.2‰ to 0.5‰, these values overlap those of the metamorphic rocks, and differ from marbles. So it can be concluded that most silicon atoms in Xiuyan nephrite came primarily from metamorphic water, and some of them were derived from the silicious band and flint concretion in marbles. Theδ34S values of pyrites and pyrrhotite which are paragenetic with Xiuyan nephrite change from 8.2‰ to 18.0‰, it suggests the sulphur in ore-forming solution was not derived from mantle, but from metamorphic water.

Abstract:Study on mineral compositions and texture of tremolite jadeware unearthed from Lingjiatan ruins was carried out, the results show that the main composition is tremolite. The study provides important basis for archeology research.

Abstract:The ancient jadewares with chicken bone-like color were unearthed at Lingjiatan, Anhui Province. In order to identify their mineral compositions, polarized microscopic observation , XRD, IR and laser Raman spectrum analyses have been conducted. The results show that the ancient jadewares mainly consist of tremolite. Compared with general nephrite, the studied jadewares are more whiter and dimmer ,and with lower hardness and density.

Abstract:The Xiuyan jade almost consists of pure antigorite,its grain size is 330nm×440nm, the grains distribute in the shape of wave along [WTBX]a[WTBZ] axis. The sequence of mineral crystallization is coarse tremolite fine tremolite-talc-antigorite. The colors are controlled by the content of TFeO and Fe2O3/FeO ratio, which are also related with transparence. Green and glossy green are original colors. Brown and red brown, which are secondary colors, were formed under oxidation conditions Colors and transparence are main quality parameters of Xiuyan jade.

Abstract:Electron microprobe and scanning electron microscope are used for examing the appearance, texture and compositions of jadeite, together with polarizing microscope, the jadeite can be appraised without damage in a fast and effective way.