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BACKGROUND Through visiting the jadeite market, the existence of inorganic material-filled jadeite is known, but there is a lack of identification basis due to rare references. OBJECTIVES To understand the identification characteristics of inorganic material-filled jadeite. METHODS Two types of inorganic materials, water glass and silica sol, were used to fill low-grade jadeite in the simulation experiment. Conventional gemological tests, fluorescence image observation with DiamondViewTM, Fourier transform infrared (FTIR) spectroscopy, and laser-induced breakdown spectroscopy (LIBS) were used to test the inorganic filled jadeite samples. RESULTS The transparency, color, density and structure of jadeite were improved after filling. Under the DiamondViewTM, the jadeite particles in the sample showed green fluorescence, and the filling around the cracks and between the particles displayed blue fluorescence with non-uniform distribution. Mid-infrared reflectance spectrum analysis showed that the spectra of silica sol and water-glass were slightly different from each other. The absorption peaks of the samples filled with inorganic materials at 1162cm-1, 1070cm-1, 949cm-1, 579cm-1, 529cm-1 and 470cm-1 gradually weakened, and the peak shape gradually became smooth or disappeared. In addition, the differences between the jadeite and inorganic filled jadeite can be determined by the near-infrared spectral morphology and the shape of the absorption peak changed in the range of 7062cm-1, 5204cm-1 and 4537cm-1. The laser-induced breakdown spectroscopy demonstrated that the content of the silicon in the jadeite filled with silicon sol or sodium and potassium water-glass was higher. The high potassium content was an important feature for the jadeite filled by sodium and potassium water-glass. CONCLUSIONS The samples effect of the simulation experiment needs to be improved, but the identification characteristics of the filled jadeite with inorganic materials are recognized, which has caused a further breakthrough in the enhancement and treatment of jadeite identification.

BACKGROUND The Marange diamond deposit in Zimbabwe is characterized by producing mixed-habit (octahedral and cuboid) diamonds. Graphite inclusions in these diamonds only exist in cuboid sectors. The morphological and distributional characteristics of graphite inclusions and the abnormal birefringence and strain characteristics of diamonds can reflect the geological process experienced by diamonds from the beginning of crystallization to being transported to the Earth's surface. Therefore, the study of diamonds and graphite inclusions in Zimbabwe can provide comparative data for diamonds from other deposits. Besides, due to the peculiarity of growth habits, detailed analysis would be of great value to help understand the behavioral differences of diamonds with different growth habits in geological processes. OBJECTIVES To determine if graphite inclusions in Zimbabwean diamonds are syngenetic or epigenetic, and to reveal the relationship between graphite inclusions and the infrared absorption spectrum, Raman scattering spectrum as well as birefringence and strain characteristics of diamonds. METHODS The growth structure and growth sectors of Zimbabwean diamonds were observed by DiamondViewTM image system. The morphological and distributional characteristics of graphite inclusions and abnormal birefringence in diamonds were analyzed by scanning electron microscopy (SEM) and polarized light microscopy. Analysis of distribution and relative concentration of impurity elements in different growth sectors was conducted by infrared spectroscopy. Strain characteristics of diamonds in different growth sectors were analyzed by Raman spectroscopy and projection diagram of corresponding results. RESULTS Graphite inclusions in cuboid sectors of Zimbabwean diamonds were syngenetic-epigenetic inclusions located in directional elliptical cracks. According to infrared spectra of different growth sectors, cuboid sectors showed stronger infrared absorption related to elemental hydrogen, while octahedral sectors showed stronger absorption related to elemental nitrogen. This enrichment of different impurity elements leading to abnormal birefringence was mainly related to cracks and different growth sectors in diamond. The Raman shift of LO=TO band in octahedral sectors was 1332.05-1332.20cm-1, the FWHM was 4.21-4.37cm-1, which corresponded to stress of 0.06-0.27GPa. The Raman shift of LO=TO band in cuboid sectors was 1331.93-1332.47cm-1, the FWHM was 3.67-4.08cm-1, which corresponded to stress of 0.01-0.64GPa. In general, the residual stress and strain were greater in cuboid sectors. CONCLUSIONS The determination of the orientation of graphite inclusions in mixed-habit diamonds in Zimbabwe, provides new evidence to prove their syngenetic-epigenetic nature, and reveal the difference in the strain characteristics of diamonds in the two growth regions. This research is helpful for understanding the formation environment of diamonds in Zimbabwe and of different diamonds. The differences in physicochemical properties are of great significance.

Hydrogen-related infrared absorption bands in natural diamonds have been extensively investigated and widely used to identify natural, treated, and synthetic diamonds grown by high pressure and high temperature (HPHT) and chemical vapor deposition (CVD) techniques. However, the evolutional behavior of the hydrogen-related defects and the relationship between the hydrogen-related and nitrogen-related defects in natural and HPHT-treated Ib diamonds are unclear. In this article, the hydrogen-related defects, particularly the infrared absorption bands of 3107 cm−1 and 3143 cm−1 in natural type Ib diamonds and HPHT-treated natural diamonds, were systematically investigated using spectroscopic techniques. It was found that the 1405 cm−1 absorption intensity was directly proportional to the 3107 cm−1 absorption intensity; the 3143 cm−1 absorption intensity increased with the increase in the 3107 cm−1 absorption intensity, but there was no strict linear relationship between them. The 3143 cm−1 band was not only related to the intensity of the 3107 cm−1 but also related to the value of NC/NA in natural diamonds. When the value of NC/NA was less than one, the 3143 cm−1 band was more pronounced. After high-temperature annealing, the absorption intensities of the 3107 cm−1 and 3143 cm−1 in natural type Ib diamonds became stronger. However, in HPHT synthetic diamonds, only a 3107 cm−1 defect was introduced with the increase in the A centers in the diamonds. The difference and the detectability of the 3143 cm−1 and 3107 cm−1 bands investigated could be efficiently used to identify natural type Ib diamonds from their counterparts, including the synthetic diamonds and the HPHT-treated diamonds. [ABSTRACT FROM AUTHOR]

In this paper, the pole figures plotted from X-ray diffraction data are employed to analyze the orientation of hydroxyapatite in ivory and mammoth ivory for the first time. The results present evidence of the lamellar structure and the hydroxyapatite appeared as tabular. A preferred orientation of hydroxyapatite was revealed in terms of the calculated orientation factor and the characteristics found in the pole figures. The c-axes of hydroxyapatite are mainly oriented along the growth direction. Both a-axes are on the left of the angle bisector of Retzius. Approximately 25–30° separates the a-axes and the angle bisector of Retzius in ivory, whereas the figure is approximately 10–15° in mammoth ivory. Our work is significant in providing more accurate knowledge of the shapes and organizational state of bio-mineral crystals and providing insight into crystal formation and development in bio-mineralization. [ABSTRACT FROM AUTHOR]

The article presents abstracts on instruments and techniques in gemology which include the application and development of digital image processing in gemmology, the use of cameras and computers in photographing jewelry and the use of digital combination photography in improving images of microscopic minerals.

The article presents abstracts on gems which include a description of the three sources of high-quality aquamarine from Minas Gerais, Brazil, an analysis of the chemical composition of nephrites from China and a comparison of mechanical mining and traditional mining in Sri Lanka.

The article presents abstracts on synthetic and simulant gems which include a description of bead materials, a discussion of gemmological characteristics and identification of a kind of dyed red coral imitation and a discussion of polymerization recycling of wasted turquoise.

The article presents abstracts on gemstones which include the determination and distribution characteristics of trace rare earth elements in pearls using inductively coupled plasma mass spectrometry (ICP-MS), assessment of granitic pegmatites and a description of pearls from the lion's paw scallop.

The article focuses on a test conducted to 21 samples of black-and-white diamond jewelry using Fourier transform infrared (FTIR) and Raman spectroscopy. It is said that about 10 of the jewelry samples were found to have black synthetic moissanite. Raman spectroscopy revealed that the inclusions in black synthetic moissanite were determined as crystalline silicon. The research "Synthetic Moissanite: A New Diamond Institute" by K. Nassau et al. noted that such moissanites were not developed through a so-called seeded sublimation process.

The article presents abstracts on jewelry history which include a description of the characters of gemstones from Liangzhuang King's tomb in Ming Dynasty in Zhongxiang, Hubei Province, China and an exploration of Western lapidary tradition in geological literature.

The article presents abstracts on gem-related treatments which include the filling of fractured rubies with glass-forming additives, identification of treated chicken-blood stones and imitations and a description of three dimensional fluorescence spectra representation of natural and treated amber.

An abstract of the article "Pt Alloy Materials for Jewelry and Ornaments," by Y. Ning is presented.

The article presents abstracts on gems which include a description of a valuation model for cut diamonds, presentation of a dataset for conflict diamonds and a study on disease status of gem worker's silicosis.

The article presents abstracts on topics about gems which include the application of geochemical ratios for delineating gem-bearing sites, the distribution of microelements in Pinctada martensii and its manual nucleus inserted pearl layer, and the impact of supergene conditions on fossil ivory quality.