Hexagonal Diamond-HD (also known as Lonsdaleite) is a natural mineral found in meteorites that has attracted attention due to its unique structure and properties. Professors Bingbing Liu and Mingguang Yao from Jilin University, and Shengcai Zhu from Sun Yat-sen University, collaborated to innovatively propose the "Post-Graphite Phase Gradient Conversion method (PGPC)". This method enabled the first successful synthesis and preparation of high-purity (>95%) millimeter-sized Hexagonal Diamond-HD bulk, resolving a half-century-long challenge in this field. The Hexagonal Diamond-HD synthesized via the PGPC method exhibits excellent properties, making it highly promising for applications in ultra-precision machining, quantum information, and deep-space exploration. However, the expensive and complex equipment required, coupled with relatively small single-crystal sizes, may pose substantial challenges on the path to industrialization. Looking ahead, if the pressure window can be optimized and CVD epitaxial technology can be developed, the Hexagonal Diamond-HD could be product in large-scale industrially, thereby driving advancements in high-end manufacturing, quantum technology, and other related fields.

Taishun stone has been esteemed as "the fifth seal stone" in China, yet its mineralogical characteristics and genesis have been received relatively limited scholarly attention. The Landai Taishun stone, distinguished by its vibrant colouration, is highly prized and widely appreciated. However, the mineral components and formation mechanism of this variety remain to be comprehensively elucidated. This study employed a suite of analytical methods to investigate the gemmological and micromorphological characteristics of Landai Taishun stone samples, thereby revealing the conditions and mechanisms of the formation of the Landai within Taishun stone. Petrographic observation, X-ray powder diffraction, and Raman spectroscopy, identified the primary mineral components of Landai Taishun stone. The matrix predominantly consists of pyrophyllite with minor amounts of diaspore and kaolinite, while the Landai is composed of corundum. The pyrophyllite exhibits a mixture of 2M and 1Tc polymorphs, with the 2M type being predominant. The chemical composition of corundom in the Landai contains Ti and Fe, which are the main factors responsible for its blue colouration. The mineral component of Landai Taishun stone is consistent with that of Qingtian Landing stone. Based on the phase diagram of rock mineral assemblages and previous data analysis, the mineral component and the polymorphic properties of pyrophyllite suggest that the rock may have formed in a metamorphic environment at temperatures about 410-430 ℃, favorable for the dehydration and metamorphic transformation of diaspore into corundum. Detailed micromorphological and energy dispersive spectroscopic (EDS) analyses revealed that the Landai portion comprises newly-formed corundum, exhibiting a plate-like morphology with porous features. These features are resulted from the transformation process of orthorhombic diaspore to trigonal corundum, driven by crystal face inheritance and subsequent misalignment adjustments, providing direct evidence of the dehydration-driven transformation of diaspore to corundum.

Recently, nephrite containing pink or red minerals has appeared on the market, the former is called "Cherry Blossom Pink", and the latter is called "Carmine". For nephrite containing pink minerals, some researchers suggested that the pink colour may be caused by Mn-bearing epidote, and some agreed that it might be caused by Mn-bearing zoisite. At present, no report can be found on nephrite containing red minerals. In this study, conventional gemmological test instruments, Raman spectroscopy, scanning electron microscope, UV-Vis spectroscopy and laser ablation inductively coupled plasma mass spectroscopy (LA-ICP-MS) were used to investigate the mineral components and colour origin of these two kinds of nephrite. The results showed that the colouring minerals in these kinds of nephrite samples are Mn³⁺-bearing zoisite(pink) and Mn³⁺-bearing clinozoisite(red), respectively, and their colours were mainly caused by the d-d transition of Mn³⁺ at the M3 site. By Raman spectroscopy, two minor minerals, nesquehonite and native sulphur, were found in the nephrite containing red minerals for the first time.

In recent years, a novel gemstone named "Feizhoucui", originated from the Barberton Makhonjwa Mountains in Africa, has emerged in the jewelry market. To date, there have been limited reports on its gemmological characteristics. To investigate the differences between "Feizhoucui" and other types of quartzite jade and to provide a scientific foundation for its identification, our research team collected both rough material and finished product samples of "Feizhoucui". The gemmological characteristics of the samples were studied using conventional gemmological testing instruments, super-resolution microscope, thin section observation under polarized light microscope, scanning electron microscope(SEM), electron microprobe(EPMA), infrared spectroscopy(FITR), Raman spectroscopy, X-ray powder diffraction(XRD) and energy dispersive spectroscopy(EDS) analysis. The results indicated that "Feizhoucui" is a kind of quartzite jade, with α-quartz as the main mineral component, exhibiting a granular structure and forming a compact aggregate of cryptocrystalline-micrystalline quartz. The green inclusions are mainly mica minerals, possibly illite, while metal inclusions are predominantly pyrite. The transparent inclusions are mainly barite. As an emerging gemstone, "Feizhoucui" has great development prospects in the jewelry market and the norms of the commercial and trade market need to be further improved to promote the sustainable and healthy development of the "Feizhoucui" industry in the future.

Colour is an important factor in evaluating the quality of pearl and directly affects its value. But definitive conclusion about the pigments of pearls has not yet been determined. During the growth process, the colour of pearl may be affected by its mussel. In order to study the relationship between pigments in pearls and mussels, Hyriopsis cumingii and its non-nucleated pearls were selected and their Raman spectra and excitation-emission matrix (EEM) spectra were collected. The theoretical Raman spectra of possible pigment structures were calculated by quantum chemistry. The results show that the Raman spectral characteristics of pearls of different colours are similar but also different. The similarity is that they all present the characteristics of polyene pigments: they all have the stretching vibration of C=C double bond and the stretching vibration of C-C single bond. While the Raman peak positions of pearls with different colour perform different. This is due to the different conjugated chain lengths of polyene pigments. The polyene pigments in orange yellow pearls and purple pearls contain 10 C=C double bonds and 12 C=C double bonds, respectively. In terms of EEM spectral characteristics, the darker the pearl colour, the weaker the fluorescence intensity. The fluorescence centers are located at 284 nm/340 nm. The Raman spectra and EEM spectra of freshwater pearls and Hyriopsis cumingii shells are almost identical, indicating a high degree of similarity in their composition. It is speculated that the secretion and metabolism of pigments in the biomineralization process of the two are very similar.

Natural blue diamonds are produced in very small quantities and command extremely high prices, mostly appearing in the auction market. With the increasing demand for blue diamonds, some synthetic or colour modified blue diamonds came into people's view. At present, common boron-doped blue diamond synthesized by high temperature and high pressure (HPHT) method tend to have a cross-shaped colour distribution characteristic of growth zoning. Irradiated type Ia blue diamonds display blue-green hues controlled by the relative intensities of N3 and GR1 colour centers. Irradiated type Ⅱa diamonds primarily show GR1-dominated colouration with GR2-8 colour centers as auxiliary contributors, so we can't control the intensity of the colour center in an artificial and quantitative way, which results in the colour being unstable. Diamond synthesized by chemical vapor deposition (CVD) has distinct advantages in controlling doped boron element concentration and maintaining uniformity and consistency. However, due to the difficulty of its growth, there are few reports of blue diamonds synthesized by CVD. In this study, a blue diamond synthesized by CVD was performed a series of optical non-destructive characterization tests by magnification examination, ultraviolet-visible spectrophotometer, infrared spectrometer, Raman spectrometer, and photoluminescence spectrometer. Comparing with irradiation modified and HPHT blue diamonds, this boron doped blue diamond synthesized by CVD was similar to natural blue diamonds in colour, with a more uniform colour distribution, clean inclusion, and a few feather and dark substances. UV-Vis spectra showed that the absorption features of the CVD synthetic blue diamonds are similar to the natural blue diamonds but distinct from the GR1 center absorption band (741nm) in irradiation-treated diamonds. The infrared spectra revealed the sample to be a type Ⅱ b diamond. The boron-related absorption peaks at 1 290 cm^-1 and 2 458 cm^-1 differed from the 2 455 cm^-1 and 2 802 cm^-1 peaks observed in natural blue diamonds, as well as the 1 450 cm^-1 peak associated with the H1a defect center in radiation-treated blue diamonds. Additionally, fluctuations in the three-phonon region (>3 000 cm^-1 ) suggested a high boron content. Raman spectra exhibited 1 332 cm^-1 diamond intrinsic asymmetry peak resulting from boron doping. Photoluminescence spectroscopy tests revealed the presence of [NV]⁰ defects (575 nm), [NV]^-defects (637 nm), and [SiV]^-defects (737 nm).

Fluorite is not only an important industrial mineral, but also a major species in the jewelry and mineral collection market. In recent years, with the diversification of demand in the gemstone jewelry market, fluorite has been widely used to make faceted gemstones, beads, bracelets, and other forms of jewelry. Fluorite is a common and easy to be synthesized material. Synthetic fluorite sometimes appears in the mineral collections and gem markets. Based on the identification demand of natural and synthetic fluorite, through microscopic observation, femtosecond laser ablation plasma mass spectrometer (fs-LA-ICP-MS), X-ray fluorescence spectrometer (XRF), ultraviolet-visible absorption spectrometer (UV-Vis), infrared spectrometer (FTIR), and photoluminescence spectrometer (PL), inclusion, optical properties, chemical compositions, and spectroscopy characteristics of natural fluorite and synthetic fluorite samples were obtained. Microscopic observation shows that there are no obvious inclusions in synthetic fluorite samples, while natural fluorite samples contain a large amount of gas-liquid inclusions. By fs-LA-ICP-MS, the Nd and Eu contents in synthetic violet fluorite and colourless fluorite samples reach 775.13×10^-6-832.63×10^-6 and 15 173.88×10^-6-16 674.97×10^-6, respectively, significantly higher than those in natural fluorite samples, such amount of Nd and Eu can be detected by XRF and makes it easy for identification. In UV-Vis spectra, synthetic fluorite samples shows obvious absorption and fluorescence peaks caused by doped REE, while natural fluorite samples show nothing obvious in their spectra. FTIR shows a large number of vibration peaks related to CO₃^2-, CO₂, hydroxyl groups, and water in natural fluorite samples, while synthetic fluorite samples do not, which is a useful character to distinguish whether fluorite is natural or not. The PL spectrum indicates that synthetic fluorite has a higher content of various REE than that in natural fluorite, and multiple REE in different valence states produce different fluorescence peaks, resulting in a more complex PL spectrum than that in natural fluorite. Moreover, the Eu²⁺ transition peak intensity of synthetic colorless fluorite samples doped with a large amount of Eu is significantly higher than that of natural fluorite, which can be used to assist in the identification of fluorite's naturalness.

Recently, a kind of imitation, whose appearance is very similar to that of agate from Yanyuan has appeared in the market. In order to determine its mineral components, chemical compositions and spectral characteristics, the conventional gemmological test methods, Fourier transform infrared spectroscopy(FTIR), Raman spectroscopy, X-ray fluorescence spectroscopy(XRF), ultraviolet-visible spectroscopy(UV-Vis) and other testing methods were used. The results show that the density of the imitation sample is greater than 2.70 g/cm³, and it can be easily scratched by a knife, and blistered by drops of hydrochloric acid. It has a fine structure, and has black dots of varying sizes sporadically distributed inside. Infrared spectra and Raman spectra show that it has the characteristic peaks of barite, calcite and epoxy resin. X-ray fluorescence spectra show that the main elements are Ba, Sr, S, which are consistent with barite. UV-Visible spectra show that the colouration of the pink part may be related to hematite, and the colouration of the yellow-green part may be related to the combined action of goethite and Cu^{2 +}, which is similar to the colouration mechanism of pink and yellow-green colours in natural agate from Yanyuan. Based on the analyses, this kind of "Yanyuan agate" is actually a mixture of barite, calcite and epoxy resin. In daily identification, it can be identified rapidly based on conventional gemmological features, and the spectroscopic features can help to further determine the mineral components of the imitation. According to GB/T 16553-2017 Identification of Jewelry and Jade, it is recommended that the terms "agate imitation" should be used instead.

Tungsten and rhenium doped in gold jewelry can be distinguished by their characteristic peaks using X-ray fluorescence spectroscopy. By magnifying the surface of this kind of gold jewelry samples under a metallographic microscope, multiple silver white metallographic structures were found. Following grinding and polishing, X-ray flowrescence spectra showed obvious characteristic peaks of rhenium and tungsten, which confirmed the presence of the two elements, along with other impurity elements.Standard calibration curves for rhenium and tungsten were established using inductively coupled plasma optical emission spectrometer(ICP-OES). The results showed that the recovery rates of rhenium at the test wavelength of 221.426 nm and tungsten at the test wavelengh of 239.709 nm as the analytical spectral lines were between 95% and 105%, with the relative standard deviations below 2%. During study, it was found that after uniform sampling and digestion testing, the concentrations of rhenium, tungsten, and other impurities were determined, and the difference is subtracted to obtain the gold content.

The Ottoman Empire, capitalizing on its geopolitical advantages, emerged as a pivotal center for East-West trade and reached its zenith in the 16^th century. A substantial volume of Chinese porcelain was entered into the empire via the Silk Road trade network and collected by the Sultan's royal household. This influx inspired local craftsmen to redecorate these porcelains using a unique gem inlay technique. Today, these gem-inlaid porcelains, accounting for about 3% of the Chinese porcelain collection in Topkapi Palace Museum in Turkey, are typical examples of cultural symbiosis and aesthetic reconstruction within civilizational exchanges, which provieds a valuable empirical sample for "Belt and Road" historical research. This study focuses on 273 gem-inlaid porcelains from the Topkapi Palace Museum, employing observational method, along with historical literature review and iconographic studies.It analyzes the acquisition routes, craft aesthetics (including material features, decorative patterns, and inlay methods), and the reasons for redecoration. The aim is to explore the technical modifications, cultural translation logic, and social functions of Chinese porcelain by Ottoman craftsmen. The research reveals that Ottoman craftsmen utillized the "mesh covering method" and "star-like dotting method" for gem inlay, transforming the Chinese porcelain into imperial treasures integrating Islamic art elements. This process facilitated the functional localization (e.g. converting wine vessels into ablution utensils) and the reconstruction of cultural symbols (e.g. the symbolic meaning of tulip-patterned metal plates).Additionally, the study also differentiates between gem inlay and mounting techniques. The transformation of Chinese porcelain by Ottoman craftsmen not only enhanced the practicality and artistry of the objects but also provided a new perspective for studying the phenomenon of "cultural symbiosis and aesthetic reconstruction" in Sino-Western exchanges.

The fish-shaped jade, as an unique component of ancient Chinese jade artifacts, embodies rich historical and cultural connotations. Its origins can be traced back to the Neolithic Age, and after thousands of years of evolution, it has become a distinctive artistic expression among ancient jade artifacts. With the continuous unearthing of fish-shaped jade artifacts, numerous studies have proliferated, covering topics such as the origin and periodization of fish-shaped jade, their functions, shapes and decorations. These research findings provide a wealth of physical materials for studying the economy, culture, social customs, and carving techniques from the Neolithic Age to the Shang and Zhou dynasties, which have reflected the pursuits and spirit of the society at the time, embodided the aesthetic needs of the ancient people, and filled the gaps in historical documents.This study employs the dual-evidence method and documentary analysis, integrating archaeological discoveries and previous research findings, to explore the function, form, and symbolism of fish-shaped jade artifacts unearthed since the Shang and Zhou dynasties. The results indicate that fish-shaped jade artifacts may have originated from primitive religious worship. During the Shang and Zhou periods, their functions diversified, serving as burial objects, ornaments, and tools. In terms of symbolism, the fish-shaped jade artifact was not only a representation of fertility worship but also a medium bridging the realms of life and death. Additionally, the unique form of the fish-shaped jade artifact, the "fish-dragon", later evolved into the "fish-dragon play", and gradually became a regional folk symbol over time.

The Ming Dynasty represented a peak in the utilization of coloured gemstones in China. During this period, coloured gemstones were not only abundant but also extensively employed. Functionally, they served not only as decorative items but also occasionally played a role in Yansheng (warding off evil spirits and seeking good fortune) within tombs. Current evidence indicates that the application of gemstones for these purposes in Ming Dynasty tombs primarily depended on their quantity and colour, as well as their placement and arrangement. This study employs a research method that cross-verifies archaeological findings with historical records, leading to the conclusion that the phenomenon of using gems to ward off evil spirits and seek good fortune in tombs was formed under the joint action of Chinese five elements doctrine, religious concepts, and funeral customs during the Ming Dynasty. Furthermore, this phenomenon is closely linked to factors such as economic and trade activities, as well as the social status and financial capabilities of those interred. Meanwhile, the analyses show that the gemstones considered to be dislodged from artifacts in archaeological excavation reports may not be dislodged, but were intentionally placed for a specific function.

With the rapid development of China's social economy, the jewelry consumption market has undergone a notable transformation in its demand structure. As a key category within the precious metal jewelry sector, gold jewelry occupies a central position and accounts for a significant sales share in the jewelry industry. Moreover, it represents an essential growth point for corporate profitability. Currently, gold jewelry that integrates traditional cultural elements and aesthetic connotations is highly favored by contemporary consumers. Nevertheless, due to the continuous fluctuation of gold raw material prices, the gold jewelry industry is confronted with novel challenges and development opportunities. In this study, the authors use research approaches including literature review, market analysis, and case studies, to chronologically sort the developmental trajectory and technological evolution of gold jewelry in China from the Xia, Shang, Zhou dynasties to the present era.It summarizes the craftsmanship characteristics of various historical periods, and investigates the shifts in the current gold jewelry consumption market.Meanwhile, in response to the bottlenecks encountered in the progress of China's gold jewelry industry, this article proposes a value enhancement pathway for its development, emphasizing the cultural confidence, artificial intelligence generated content (AIGC) technology assistance, and brand operation. These insights aim to provide innovative ideas and references for the sustainable development of the industry.

The application and practice of artificial intelligence (AI) technology in the general education course of gemmology in higher education aims to address the challenges faced by traditional gemmology teaching, enhance course effectiveness, and improve students' learning experience. Based on an analysis of the main issues encountered in teaching jewelry and gemmology-related general education courses, this study explores the specific applications of AI technology in gemmology courses, including digital resource development, knowledge graph construction, and AI-based personalized learning and teaching evaluation practices. It also discusses the potential and limitations of AI in gemmology education and proposes that future applications should focus on the organic integration of technology and subject content, strengthen the cultivation of students' critical thinking, adhere to educational ethics, and ensure that technology supports teaching without replacing the importance of traditional cultural education.