Abstract:A new kind of black nephrite was found in Dahua Yao Autonomous County, Guangxi Zhuang Autonomous Region. In this paper, gemological, petrological and mineralogical characteristics of the nephrite were studied. The results show that the fine and moist nephrites with micro-interwoven fibers and micro-prismatic textures are composed mainly of actinolite and ferroactinolite, and contain typical minor mineral stilpnomelane together with pyrite and pyrrhotite. As a new genetic type of dark nephrite deposit, the Dahua black nephrites occur in the inner contact zone between diabase and surrounding carbonate rocks and were formed by hydrothermal metasomatism after skarnization. The Dahua black nephrites have almost the same gemological characteristics as the black nephrites from other places, whereas the Dahua black nephrites with slightly higher density are iron-richer in composition and consist mainly of minerals with high iron content. The color of Dahua black nephrites is caused by actinolite-ferroactinolite with high iron content.

Abstract:The jasper produced in the Cassiar mine of Canada and sold in China's market was studied in this paper. The jasper samples were tested by electron microprobe analysis (EPMA). The jasper is mainly composed of tremolite. The conventional gemological properties and characteristics of the jasper samples are consistent with the data of GB/T16553-2011 Jewelry National Standard. Tests show that the Vickers microhardness of the jasper is between 813.6～605.7 N/mm². The IR spectra were obtained by means of squash method and powder Infrared method, and the results show that the former method could provide more information of IR spectra for jasper samples.

Abstract:In this paper, a new nephrite deposit was reported from Sangpiyu Village of Xiuyan County, and an analysis of its gemological characteristics, mineral assemblage, chemical composition was carried out. Modern techniques such as microscope, electron microprobe analysis, chemical analysis, and isotope analysis were employed. The results show that the nephrite from Sangpiyu is mainly composed of tremolite (> 94%), with minor apatite, chlorite, epidote, serpentine, calcite and limonite. Tremolite texture is characterized by microcrystalline-cryptocrystalline aggregates. It is concluded that the nephrite deposit in Sangpiyu Village is a kind of metamorphic hydrothermal deposit.

Abstract:By means of microscopic observations and infrared spectroscopic analysis of "skin" and "flesh" of cut items of the Hetian placer nephrite, the authors studied their characteristics and relationships. Features of the skin include "sweat pores", sand hole, crack, stony appearance etc. Inside the skin are stony appearance, impurity, iron flower etc. Some relationships between "skin" and "flesh" are summarized as follows: diameter of the sweat pore reflects its host quality: the finer, the better. The sand hole indicates weaker-weathered or softer minerals in the interior part, for example, the appearance of pyrite often produces a hole at the surface. Stony appearance exists in both interior part and exterior part and affects the quality greatly; the existence of starry distribution will apparently affect the homogeneity. The component tremolite can also appear as stony appearance with its texture different remarkably from surrounding jades. Different sorts of minerals such as diopside and calcite can also display stony appearance. The existence of cracks is not always a bad thing, as bright-color may occur along the crack surface. The results achieved by the authors have some significance for identification, evaluation and design. Nevertheless, these relationships deserve further investigation.

Abstract:With its strong colors, delicate structure and special optical effects, the green Hualian nephrite of Taiwan is very popular among consumers. This paper deals with the gemological and mineralogical characteristics of green nephrite on the basis of basic test data and mineral compositions. Scientific, comprehensive and systematic research has a great significance for improving the scientific value and visibility of Hualian nephrite from Taiwan. The color of green nephrite ranges from light green to dark green, being relatively pure but distributed unevenly. Black metal mineral inclusions can be recognized, which have greasy-silky luster and are translucent to opaque. The green nephrite has refractive index of 1.61, relative densities from 2.96 to 3.02 g/cm³, and hardnesses from 6 to 7, and mainly consists of tremolite or actinolite, with minor grossular, chromite and chlorite. Electron microprobe analysis shows that the composition of green nephrite is characterized by relatively high values of MgO, SiO₂, CaO,comparatively low FeO, and minor amounts of Cr₂O₃, MnO, K₂O, Na₂O, Al₂O₃, TiO₂. The color of green nephrite has a positive correlation with the content of FeO. In addition, when the nephrite contains grossular, its color will become more bright.

Abstract:Mineralogical characteristics of Hongsi Inkstones from Linqu in Shandong Province were studied using petrographic observation, infrared spectra, X-ray powder diffraction (XRD) and electron microprobe analysis (EMPA). The inkstone comprises mainly microcrystalline calcite, subordinately quartz and dolomite, and minor hematite, rutile and muscovite. Hematite is the main factor responsible for the differences of colors. Impurities in Hongsi Inkstone, commonly known as stone eyes, stone bars and ink marks, are also composed of calcite as well as minor quartz and dolomite, with the trace minerals responsible for the differences of impurities.

Abstract:Recently, a new kind of gem product whose business name is "Cuihua Jade" appears in the jewelry market. It contains purple, green and white parts and is easily mistaken for nephrite. The authors chose three samples, used conventional gemological methods and polarizing microscope to investigate their gemological characteristics and mineral components, and then employed XRD and EPMA to emphatically probe into their mineral components. The results show that the "Cuihua Jade" is a kind of multi-mineral aggregate jade and of metasomatic origin, with its main mineral components being diopside, tremolite, fluorite, quartz, plagioclase and calcite, in which the tremolite exhibits network distribution in the sample. The refractive index of the green part is 1.61 (point measurement), and that of the purple part is 1.43 (point measurement). The average density is about 3.03 g/cm³. The color of the sample is mainly caused by purple fluorite and green tremolite.

Abstract:The mineralogical characteristics of copper pectolite samples from Dominican Republic were studied and analyzed. The observation under microscope shows that copper pectolite has a dense and fibrous structure, with the fiber length being about 0.01～0.02 mm. X-ray diffraction determination shows that there exists no other mineral phase except pectolite in the copper pectolite sample, which is in agreement with the result of energy disperse spectrum analysis. However, no conspicuous difference is observed in infrared spectra and ultraviolet-visible absorption spectra among the copper pectolite samples with different color tones.

Abstract:Arizona State in southwest USA is one of the main producing areas of high-quality turquoises. Natural, Zachery-treated and plastic injection processed Sleeping Beauty turquoises were investigated with the purpose of analyzing their gemological and mineralogical characteristics and explaining the causes of their beautiful color and high hardness. These characteristics were studied by such methods as conventional gemological tests, ultraviolet-visible spectrophotometry, XRD, infrared spectrum, microscopic observation, and WDXRF analysis. The results confirm that, compared with turquoises from other producing areas, the Sleeping Beauty turquoise from the USA has more compact structure and higher Cu²⁺ content, which can explain its higher hardness and purer color. Zachary and injecting process-treated turquoise has more compact and stable structure. WDXRF test of Zachary-treated turquoise shows a visible increase of K element. The infrared spectrum of plastic injection-treated turquoise shows a characteristic weak absorption band at 1 735 cm^-1, caused by the ν(C=O) stretching vibration of the organic compound.

Abstract:Omphacite jade is a special species of jade consisting mainly of omphacite. Ouyang Qiumei define it as a kind of single mineral jade composed of more than 90% omphacite, with special attributes characterized by blackness in the reflecting light, greenness in the transmitted light, and strong vitreous luster. In recent years, the high-quality omphacite jade has been much sought after by the market and collectors because of its delicate texture, strong vitreous luster, dark green to black color under the reflection light and bright green color under the transmitted light. This paper discusses the main structural characteristics of omphacite jade and its mineral particle size, morphology and fracture development that remarkably influences the transparence of omphacite jade.

Abstract:In order to determine the exact radioactive level of rough jadeites with the purpose of clearing people's minds of doubt concerning radioactivity of gems and jades, the authors analyzed the specific radioactivities of natural radionuclides such as ²²⁶Ra, ²³²Th and ⁴⁰K in ten samples from three different types of rough jadeite using low background multichannel gamma spectrometer (HPGe). The results show that the specific radioactivities of radionuclides concerned are lower or only a slightly higher than the minimum detectable limits, and both internal exposure index (I_Ra) and external exposure index (I_γ) of the samples are by far below relevant national provision of radionuclides in building materials. These data indicate that the radioactive level of rough jadeites is rather low and corresponds to natural radioactive background, and hence there is no harm of radioactivity.

Abstract:The differences between green beryls from the Kokotokay No. 3 pegmatite and aquamarines from the Azubai area in Xinjiang were investigated by means of laser Raman spectroscopy. Some conclusions have been reached: ① Gem-grade beryls from Azubai No. 328 and No. 528 pegmatite veins are characterized by high content of TypeⅠchannel water, and beryls from Kokotokay No. 3 pegmatite show interchanging properties. Beryls formed during early crystallization (zone Ⅰ and zone Ⅱ) and in the magmatic system that is comparatively rich in water (zone Ⅳ) feature predominantly TypeⅠchannel water, whereas beryls from the more evolved textural zones, i.e., zones formed at magmatic and magmatic-hydrothermal stages (zone Ⅲ and zone Ⅴ, respectively) comprise mainly TypeⅡchannel water. ② The discovery of cryolite inclusions in Kokotokay No. 3, Azubai No. 328 and No. 528 pegmatite veins indicate that the pegmatitic magmas have a relatively high content of F. ③ The types of channel water in beryls (TypeⅠand TypeⅡwater) and their relative proportions are subject to the magmatic-hydrothermal evolution of the pegmatites as well as the formation conditions. The pegmatitic magma system that is relatively oxidized forms primarily beryl minerals, while the system that is relatively reduced and rich in water is favorable for the formation of aquamarine.

Abstract:Changle in Shandong Province is one of the main producing areas of sapphire. This paper deals comprehensively with the characteristics of Shandong star sapphire and the mechanism governing the starlight and light spot exhibited at the surface of the Shandong star sapphires. The authors listed the varieties of needlelike inclusions and expounded the special characteristics of Shandong star sapphires, such as the composite luster, the weak magnetism and the newly-discovered color-causing ions. Discussion was also given to the luminescence of Shandong sapphire, the discovery of the elements which cause color variation of Shandong yellow sapphire in different lights and the classification, gradation and evaluation principles of this kind of sapphire.

Abstract:Colored diamonds belong to a kind of extremely rare ore resources and gemstone wealth. This paper describes in detail the main producing areas of colored diamonds in China and the geological characteristics of the orebodies and, from the angles of primary deposit and placer, deals with geological characteristics of colored diamond orebodies in such provinces as Shandong, Liaoning, Hunan and Guizhou. According to the results achieved, China's colored diamonds are characterized by extremely rare content, varying crystal completeness, existence of inclusions in most diamonds, well-developed crystal corrosion and high transparency. China's colored diamonds represented by those from Shandong have relatively large grain sizes and hence can be applied as high-end gemstones. It is also pointed out that the value of China's colored diamonds has not been fundamentally tapped, and their market value has not been fully manifested yet.

Abstract:Mineralogical and gemological characteristics of samples of the Ningqiang coral jade from Ningqiang County of Shannxi Province were identified, analyzed and studied. The results show that the Ningqiang coral jade is a kind of coral fossils formed by the infilling of coral bones and carbonate minerals in its pores, and mainly comprises calcite, with a few other minerals. Its densities vary in the range of 2.71～2.72 g/cm³,with refractive index being 1.50. In spite of its low Moh's hardness, the Ningqiang coral jade is an excellent type of jade due to its fine matrix, various colors and laminations. It is thus held that, with its unique structures and laminations, this kind of jade is suitable for producing plain ornaments and handicrafts.

Abstract:Using the Elementar vario PYRO cube elemental analyzer, the authors accomplished high precision test on mass fraction of ambers from different producing areas, and then analyzed the differences between their compositions. After that, by using IRAffinity-1 Fourier transform infrared spectrometer, the authors adopted the transmission method to obtain the absorption spectra. Based on the comparison and analysis of the spectra, the authors found that during the petrifaction of the amber there existed no obvious exchange reaction between the hydrogen in the amber and that surrounding the amber. The infrared absorption spectrum can be used as the important basis to identify the ambers from different producing areas.

Abstract:Amber is a kind of organic gem, and its ecological and scientific values attract increasing attentions. Amber is the fossil form of plant resins. This paper reviews the types and the geohistorical distribution of modern and extinct resin-producing plants. Modern resin-producing plants include conifers and many families of angiosperms. Amber produced by modern conifers such as Araucariaceae can be traced to the late Triassic and early Jurassic; however, the most abundant records are from the middle Cretaceous to Miocene. From Eocene onwards, ambers from angiosperms became dominant in deposits. The extinct resin-producing plants include cordaitaleans and medullosan seed ferns which flourished in the Carboniferous and Permian, as well as several groups of extinct coniferous gymnosperms which appeared from the Carboniferous onwards. The most ancient amber is from late Carboniferous strata (ca. 320 Ma in age). Amber contains abundant plant and animal fossils, which provide valuable materials for the study of evolutionary history of organisms on the Earth.

Abstract:Amber is a kind of organic substance made of pine resin formed by the geological process in Mesozoic Cretaceous-Cenozoic Tertiary strata. Currently, there are many amber localities all over the world, such as countries along the Baltic Sea, Mexico, Dominican Republic,Fushun in China, Kuji and Iwaki in Japan, Thailand, Australia, and New Zealand. However, the burmite from Myanmar is the only Cretaceous amber with commercial value. The principal resource of burmite is in the Hukawng Valley, which is situated between Myithyina and Tanai in Kachin State. In this study, LEICA M125 stereoscopic microscope of China University of Geosciences (Beijing) and LEICA EZ4D microscope (equipped with camera) of Insect Research Laboratory in Beijing Forestry University were used to observe the inclusions of the burmite sample. About 20 inclusions were observed, which belong to 15 species of Arthropoda. Most of them belong to insecta, like the Tenthredinidae of Hymenoptera and the Tipulidae of Diplura. However, some species remain undetermined.

Abstract:Recently, dyed opals from Ethiopia are often seen in the market. The Ethiopian dyed opals with three kinds of common colors were studied in this paper using ordinary gemological testing methods, spectrum analysis and other methods such as absorbent experiment, soaking fading experiments and soaking dye experiments. The results show that these Ethiopian dyed opals are mainly dyed by soaking the opals in chemical pigments solutions of different colors in consideration of their relatively bigger porosity and stronger dye absorption. The surfactant containing carboxylate ions or hyperdispersant (e.g. phthalate) is often used to disperse pigments granules more evenly. The identification characteristics of Ethiopian dyed opals are as follows: ① Semitransparent to semitranslucent, dyed orange and blue samples have strong to weak play of color, whereas dyed black samples are mostly grayish blue or yellowish gray in color with strong red, yellow, green, and blue play of color, as well as strong to weak red tone and uneven dye concentration phenomenon under transmitted light. ② The absorbent of dyedopals from Ethiopia is as strong as that of the natural ones; once they absorb water, the density and weight both increase obviously, the transparence becomes stronger, and the play of color may be enhanced or weakened; the densities of dyed opals from Ethiopia vary in the range of 1.63～1.86 g/cm³, and the refractive index is 1.40, which are consistent with the data of natural ones from Ethiopia but are lower than corresponding data of opals from Australia and Mexico. ③ Observation under high-power microscope shows that the colors of the dyed opal samples are unevenly distributed: there are dye dots, dye spots, dye lumps in the inner part, more obvious dye concentration along edges, scratches and pits at the surface. ④ The solvents will change color when dyed opals are soaked in them. ⑤Roman spectrum shows that dyed opals exhibit strong fluorescent background, weak 3 362 cm^-1 peak caused by heat effect, and weak Raman scattering peak. ⑥ UV-Vis absorption spectrum indicates that dyed opals are different from natural ones.

Abstract:A kind of mixture of amber and plastic resembling Baltic amber or "Mila" was recently detected by the authors in the course of testing amber samples. The samples of amber-plastic mixture are yellow or yellow-white in color, vary from transparent to opaque and occur as polished or inferior smooth round beads or hand strings with resinous luster. The samples were studied by using such means as gemological methods, infrared spectrum and Roman spectrum. The results show that these samples belong to the community of amber and plastic, with the yellow part being Baltic amber and the white part being artificial alkyl resins. The characteristics for identifying amber-plastic mixture are as follows: there are obvious boundaries between the yellow part and the white part in some samples, but without obvious boundaries in some other samples. The yellow part is characterized by convoluted lines, dense tiny bubbles group under high-power microscope, refractive index of 1.54, yellow green fluorescence under ultraviolet light, diagnostic infrared absorption spectra such as 2 927, 1 737, 1 451, 1 380, 1 257, 1 159 and 983 cm^-1, and Roman spectra such as 1655 and 1 453 cm^-1; the white part is characterized by dull appearance, blue fluorescence under ultraviolet light, the refractive index of 1.60, blue fluorescence under ultraviolet, diagnostic infrared absorption spectra such as 3 061, 1 728, 1 600, 1 580, 1 493, 1 453, 1 282, 1 123, 1 067, 745 and 701 cm^-1, and Roman spectra such as 735, 1 607, 1 460, 1 048 and 1 011 cm^-1.

Abstract:According to the internal and external filling characteristics and the shape of the secondary glass of rubies observed by the microscope, combined with the luminous phenomena of the basal plane of ruby and secondary vitreous body revealed by Diamond View^TM, the "quantity" of the filled glassy material in ruby can be judged. Filled ruby can be divided into three grades of "slight filling", "moderate filling" and "significant filling" and the author suggests that the corresponding names should be ruby with visible slight filling phenomenon, ruby with visible moderate filling phenomenon and ruby of filling treatment.

Abstract:Color origins of many gemstones and jades are related to the electronic structure and local environment of color-causing elements. X-ray absorption spectroscopy (XAS) is a strong tool to detect the local structure and chemical environment of the absorbing atom such as valence state, coordination number and bond length. Based on the effective examples of ruby, chrysoberyl, jadeite and ivory, this paper briefly describes the application of synchrotron radiation XAS to gemology and its advantages.

Abstract:The gemological characteristics of a kind of artificial "cinnabar" recently appearing in the market were studied through such testing methods as density, magnification observation, ultraviolet fluorescence, infrared spectrum and X-ray fluorescence spectrum, and the results show that the artificial "cinnabar" is composed of barite, calcite, organic matter and cinnabar of varying content.

Abstract:It is well known that the so-called "American natural turquoises" in the present market are actually mostly treated by Zachery process. By means of enlarged observation, UV-visible spectroscopy, scanning electron microscopy, X-ray fluorescence spectrometer and infrared spectrometer, the authors carried out the study of the gemology, mineralogy, chemical composition and spectral characteristics of Zachery-treated turquoise. The results showed that, due to the wide range of variation in the characteristics such as luster, structure, density and hardness of the natural turquoises, it is impossible to distinguish and identify the Zachery-treated turquoises by the conventional gemological tests and the UV - visible spectroscopy as well as infrared spectroscopy, and only the existence of the high K⁺ element content shown by X-ray fluorescence spectrometer and the observation of the crystalline phenomenon on the turquoise surface by scanning electron microscopy can be used as the accurate judgment basis of Zachery-treated turquoises.

Abstract:This paper deals with the category and publication status of Chinese jade jewelry literature, with emphasis placed on elaborating collection scope, retrieval method and jade jewelry literature collection status of nationwide famous information resource providers: CNKI, CALIS, NSTL, and National Library of China. Besides, computer-based modern information retrieval technology and methods are also discussed, which include field search, truncation search, Boolean search, and full-text search.

Abstract:Tourmaline is not only a popular colorful gemstone but also a kind of environmental mineral. This paper deals with the spontaneous polarization of tourmaline, which is responsible for such characteristics of tourmaline as surface electric field, electrolysis of water molecules, and release of negative air ions, thus making this mineral good for the environment in such aspects as absorbing heavy metal ions and degrading organic great molecular pollutants in water. When people wear tourmaline jewelry, its spontaneous polarization phenomenon is also helpful to body protection in that it has certain electromagnetic shielding effect and can promote metabolism of the human body.

Abstract:In this paper, the authors studied the mineralogical, magnetic, phase and chemical composition characteristics of IIICD iron mereorite from Nandan, and compared this kind of mereorite with Argentine IAB iron meteorite and Siberian IIB Iron meteorite that belong to different chemical types, focusing on the weathering effects. The mineralogical characteristics of the sample were observed by means of polarizing microscope, hydrostatic weighing, and scanning electron microscope, and the magnetic properties, phases and chemical composition of iron meteorites were studied through vibrating sample magnetometer, X-ray diffraction and electron microprobe spectroscope semi-quantitative test. The results show that weathering can change the mineralogical properties of iron meteorite. With the strongly weathered iron meteorites from Nandan as an example, the authors have found that the luster is weakened to earthy luster, and the relative density is reduced. Moreover, antiferromagnetic substances produced by weathering can reduce the magnetism of iron meteorite. In addition, mineral phases also change greatly with secondary minerals of iron being such main phases as goethite (FeOOH) and magnetite (Fe₃O₄). Nevertheless, below its crust of weathering, the mineral phases and chemical composition have not changed significantly, and exist as kamacite and taenite phases dominated by Fe and Ni.

Abstract:The computer-aided gem identification information system for teaching based on group grey relational grade analysis is designed for teaching reform and cultivating innovative practice ability. Computer-aided identification for gem testing is realized in judging by multispecies and multiparameters. The group grey relational analysis method improves the accuracy and reliability of the grey and reduces the required data precision in the standard state model compared with the traditional grey relation analysis method, thus achieving better gem identification capability and reliability. With popularization value, the system breaks through the traditional mode of education and provides a convenient platform for resources sharing and supplementary identification.

Abstract:This paper deals with the consumption transformation of China's gold, silver, jewelry and jade market from four aspects, i.e., the transformation of consumption structure, major consumer transformation, information dissemination and national policy. According to the data obtained in the past years and the investigation and research conducted by the author, the consumption transformation of China's gold, silver, jewelry and jade market has been proceeding rapidly and this revolution will bring huge challenge and great opportunities to jewelry practitioners, especially jewelry dealers. In this revolution, people can be the winner of this transformation as long as they can seize the opportunity and especially the core area.