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This paper analyzes and identifies the binders used in the jewel settings of the Baodian and Diexie belts excavated from the tomb of Murongzhi in Wuwei, Gansu, China. Fourier transform infrared spectroscopy (FTIR) indicated the presence of protein in the binder samples. The result of gas chromatography–mass spectrometry (GC‐MS) shows that samples from both contained hydroxyproline, a characteristic amino acid for animal glue. Principal component analysis was performed on one of the samples, and it was concluded that the binder was a mixture of hide glue and egg glue. Further analysis using scanning electron microscopy with energy‐dispersive X‐ray (SEM‐EDX) and laser Raman spectroscopy (Raman) found that a red particulate matter visually identified in the binder was cinnabar, which was apparently added to binder in order to modify the color of the jewels. This study provides a basis for the conservation and restoration of future finds of elite jewelry. It also shows how imperial jewelry was made during the Tang Dynasty. Finally, the analysis of these heraldic belts provides a key insight the life and role of an exiled prince in the Tang court. [ABSTRACT FROM AUTHOR]

Some of the poorest people in the world's poorest countries eke out a living in artisanal and small‐scale mining (ASM). Equipped with primitive tools like picks, shovels, buckets, and gold pans, they work mining valuable resources, like gold, diamonds, tin, lithium, rare earth elements, tantalum, and cobalt, and any other usable commodity, for example, sand, coal, or mica. The mining and refining processes are labor intensive and associated with a variety of health problems due to accidents, overheating, overexertion, dust inhalation, exposure to toxic chemicals and gases, violence, and illicit and prescription drug and alcohol addiction. Evident disadvantages with ASM are counterbalanced by the immense economic benefits. For many, the true scope and scale of ASM activities are unappreciated, along with the unknown health and societal impacts. Here, we set out to elucidate the scope of ASM beyond the recovery of familiar commodities, such as gold and diamonds. We adopt a holistic perspective toward health impacts of ASM, which includes unique occupational, environmental, and human/social drivers. A particular focus is poverty as a health risk with artisanal miners. They are commonly poverty‐stricken people in poor countries, ensnared by a variety of poverty traps, which take a toll on the health and well‐being of individuals and communities. ASM sometimes provides an opportunity to diversify income in the face of a decline in subsistence agriculture. However, ASM often trades one kind of generational poverty for another, coming along with serious health risks and turmoil associated with work in an informal "cash‐rich" business. Plain Language Summary: Many of the world's most valuable commodities, for example, gold, diamonds, and strategic metals, and less valuable resources, for example, sand, clay, and coal, are the products of artisanal and small‐scale mining (ASM). The miners are commonly poor people with rudimentary tools, like shovels, buckets, and pans subsisting by working shallow ore deposits. Although an inefficient mining method, the large numbers of people can contribute substantially to a country's total production. Much of this mining occurs in distant, lawless areas like the Amazon River basin or the outback in the Democratic Republic of Congo. The work is grueling and dangerous because of violence and unregulated work sites. Miners suffer from the expected collection of occupational health risks, due to, for example, accidents, chemical exposures, dust inhalation, and lifting and lugging of heavy loads. Mining communities are at risk from incidental exposures to mercury, mosquito‐borne diseases, poor sanitation, and more. Human and social problems also impact health. Our paper emphasizes poverty as a risk factor for disease, as miners are caught in poverty traps—unable to leave. Injuries and disease often must remain untreated because of costs and absent clinics. Key Points: Artisanal and small‐scale mining (ASM) is primitive with health problems determined by occupational, environmental, and social settingsASM involves 80 + countries and valuable resources, like gold, diamonds, precious stones, tantalum, tin, tungsten, and commoditiesGrueling work, poverty, illegalities, and worksites located in remote and medically underserved areas contribute to poor health [ABSTRACT FROM AUTHOR]

Sodalite‐group minerals are silicates belonging to the zeolite group hosting in their cages a variety of cations and anions. Four mineral species of the sodalite‐group are known in nature, the main difference being connected to the identity of the chemical species in the cages, particularly the sulfur molecular arrangements. Notably, the sodalite‐group minerals show different colours; lazurite, in particular, is the main constituent of the well‐known lapis lazuli, a material used throughout the human history as a precious stone or as a blue pigment for artworks. In this paper, we exploit Raman and Fourier‐transform infrared (FTIR) spectroscopy to highlight an existing connection between the chalcogen species entrapped within the samples originated from the volcanic region of Latium (Italy) and their final colour. We show that Raman spectroscopy is a very valuable tool in characterizing the extraframework content in these minerals. Further, our analysis demonstrates how the blue hue of the sodalite species is related to the S3−/SO42− relative content. We finally show how most specimen are also rich in CO2, a feature addressed by combination with FTIR spectroscopy. These findings have a particular interest not only in geology, but also in Cultural Heritage studies. [ABSTRACT FROM AUTHOR]

In this paper, the authors explore the spectral properties of a sharp emission line centered at 499.6 nm (reported previously as 499 nm) observed in the UV‐luminescence spectrum of synthetic CVD diamond gemstones. These gemstones also exhibit spectrally prompt broad blue luminescence centered at 435 nm which is similar in character to the 425 nm blue luminescence characteristic of type IIa natural diamonds. By comparing the results against synthetic CVD diamond material which has been subjected to high temperature anneals, the authors can speculate on the nature of the defect associated with this color center. Since the 499 nm spectral line has only been observed in synthetic CVD diamonds to date, the authors further propose that it can be helpful in the identification of synthetic diamonds, in particular those showing the blue luminescence signature usually associated with type IIa natural diamonds. Diamonds luminesce on exposure to ultraviolet light. This luminescence spectrum contains unique signatures which reveal a lot about the diamond's provenance. Recently the authors have observed an unusual long‐lived green luminescence signature in diamond gemstones that are known to be of synthetic origin. The authors discuss whether this spectral signature can be used as a tool to discriminate between natural and synthetic diamonds. [ABSTRACT FROM AUTHOR]

Mineral identification is the first step in gemstone characterization, which is the foundation for maintaining transparency in gemstone trading. Current techniques have complex protocols and require expensive instrumentation, severely restricting their use to trained experts or large gemological laboratories and limiting the processing speed. A simple and inexpensive automatic identification instrument can fulfill the needs of the Gemology Society. Hence, we propose a portable setup for the automatic mineral identification of gemstones based on a custom‐built 405 nm Raman spectroscopy probe system. This device enables the noninvasive mineral identification of commonly encountered loose or mounted gemstone materials in the market and generates the results in seconds. It is mechanically designed to allow safe operation under normal office conditions, and the pre‐aligned sample stage significantly simplifies the sample alignment process. Fifty‐seven types of gemstone materials in the trading market were tested with the device to prove the usability of the system. The primary purpose of this device is to automatically identify the types of minerals in the gemstones. It can also be extended to identify lab‐grown gemstones in the selected mineral species. [ABSTRACT FROM AUTHOR]

The Shigar valley of northern Pakistan is a well‐known region for holding a variety of gemstones. As the gemstone‐bearing rock, post‐collisional leucogranites, and pegmatites in Shigar valley have been sporadically researched but the detailed and updated timing record along with the source rocks were not adequate. Here, we present comprehensive U(‐Th)Pb ages, mineral, and whole‐rock isotopic analyses to investigate the petrogenetic evolution of these granitoids. The zircon, xenotime, and monazite U(‐Th)–Pb ages show crystallization of leucogranites that spanned as recent as ~7–3 Ma. The REEs with nearly smooth patterns and distinct negative Eu anomalies in all the leucogranites and pegmatites with contrasting negative Eu anomalies illustrate significantly plagioclase fractionation. These leucogranites and pegmatites have high SiO2 content showing peraluminous geochemistry. Zircon Hf isotopic composition of leucogranites, pegmatites and gneisses have εHf(t) values of −28.4 to +7.4, −24.0 to −16.5, and −13.2 to +1.8, respectively, which shows crustal origin along with the probable contamination from Kohistan‐Ladakh Arc at depths. Furthermore, monazite Nd isotopic composition of leucogranites, pegmatites, and gneisses have εNd(t) values of −22.9 to −9.5, −25.1 to −22.8, and −26.3 to −24.8, which seems purely from crustal source. The whole‐rock Sr‐Nd‐Hf isotopic composition shows that leucogranites and gneisses have 87Sr/86Sr(i) values of 0.71603 to 0.92518, εNd(t) values of −22.2 to −2.7, and εHf(t) values of −44.1 to −0.2, respectively, that also confines it to the metapelitic origin. Our results overall reveal that the leucogranites are produced mainly by the partial melting of Dassu felsic gneiss from the Karakoram Metamorphic Complex, showing signatures of the upper crustal rocks of the subducting Indian Plate and hybridized juvenile Asian crust. The input of heat for partial melting is likely to be derived either from the lithospheric mantle which followed the slab break‐off or from shear heating along Main Karakoram Thrust. Furthermore, a leucogranite sample yielded a zircon U–Pb age of 84.9 Ma, and monazite U(‐Th)–Pb age of 10.8 Ma. The in‐situ zircon Hf and monazite Nd isotopes yielded εHf(t) values of +3.6 to +10.7, and εNd(t) values of +1.0 to +2.4, whereas the whole‐rock 87Sr/86Sr(i) value is 0.70522, εNd(t) is +1.1, and εHf(t) is +4.8, respectively, which confirms it to be sourced from the nearby Kohistan‐Ladakh Arc. [ABSTRACT FROM AUTHOR]

The color of most garnets is derived from multiple color‐producing elements (chromophores). In this study we selectively isolate the ultraviolet–visible–near infrared (UV–Vis–NIR) spectra of four major chromophores (Fe2+, Mn2+, Cr3+ and V3+) by collecting and extrapolating the spectra of four representative pyrope‐almandine‐spessartine (pyralspite) garnets. In order to study the color strength of these isolated chromophores and their impact on color change in garnet, we have proposed a new quantitative definition of strength of a chromophore. With the isolated garnet chromophore spectra, hypothetical garnet spectra with various chemical compositions can be simulated. By using these hypothetical garnet spectra, the impact of each chromophore on the color change behavior in pyralspite garnet was also quantitatively studied. Most pyralspite garnets can be successfully modeled using these four chromophores, however, this model cannot adequately describe those garnets containing the Fe3+/Fe2+ intervalence charge‐transfer transitions. Finally, a comprehensive excel data processing template (Appendix 3) written with VBA macro code was generated to help other researchers calculate colorimetric parameters and color panels from UV–Vis–NIR spectrum. In the template, we provided multiple types of conversion matrices and power distribution curves of different illuminants, so that different colorimetric parameter conversion and color panel calculation from UV–Vis–NIR spectrum can be selected with different combinations based on people's preference. The user guide of the excel template can be found in Appendix 4. The detailed calculation procedures and formulae used for the excel template can be found in Appendix 5. [ABSTRACT FROM AUTHOR]

Artisanal and small‐scale mining (ASM) make up roughly 90% of the colored gemstone trade, a still untamed industry where money laundering, cartels, arms purchases, and crime run rampant while many miners prospect and dream of finding "the big one." Women make up to 30% to 50% of ASM, often in developing regions. Struggling to make a living and support their families, women miners are subject to discrimination, unfair labor practices, and poor access to rich foreign markets. Grounded in a longitudinal case study in Africa, this qualitative research examines the journey of an organization seeking to emancipate women miners through supply chains that embrace technology, provenance, and disintermediation. This research demonstrates the strategic value of emancipatory technologies for firms. Secondly, we find evidence that combinations of storytelling and digital records create multidimensional provenance that mitigates a number of supply chain risks, particularly in tainted chains. Lastly, this research extends Tang's framework for engaging marginalized populations as suppliers and producers. [ABSTRACT FROM AUTHOR]

In this work, we put forward a facile yet efficient room-temperature synthetic methodology for the smart fabrication of mesoporous nanocrystalline ZnMn2O4 in macro-quality from the birnessite-type MnO2 phase. A plausible reduction/ion exchange/re-crystallization mechanism is tentatively proposed herein for the scalable synthesis of the spinel phase ZnMn2O4. When utilized as a high-performance anode for advanced Li-ion battery (LIB) application, the as-synthesized nanocrystalline ZnMn2O4 delivered an excellent discharge capacity of approximately 1288 mAh g−1 on the first cycle at a current density of 400 mA g−1, and exhibited an outstanding cycling durability, rate capability, and coulombic efficiency, benefiting from its mesoporous and nanoscale structure, which strongly highlighted its great potential in next-generation LIBs. Furthermore, the strategy developed here is very simple and of great importance for large-scale industrial production. [ABSTRACT FROM AUTHOR]

Tanzanite is the blue to violet‐blue variety of the sorosilicate zoisite; its colour is due to vanadium substitution of aluminium in the octahedral sites and is proved to appear after natural or artificial heating to approximately 500°C. Its colour makes it a highly appreciated gemstone, for this reason often imitated or thermally treated with the aim of enhancing its hue. Tanzanite loose gemstones are easily identified by classical gemmology methods that are not always applicable to mounted jewels. At the same time, zoisite Raman spectra are rarely reported in literature and never with a systematic approach. In this work, zoisite samples and cut tanzanite gemstones were considered, with the aim of filling this gap by addressing different methodological aspects. Namely, the orientational effects were investigated to explain the spectral variability, the photoluminescence bands were differentiated from the Raman signals using different excitation wavelengths, and the effectiveness of portable instrumentation in the correct identification of tanzanite was evaluated. The results are encouraging, showing that zoisite is revealed, notwithstanding orientational effects, by both portable and laboratory Raman instruments with comparable performances, opening the way to an effective identification of mounted tanzanite gemstones. Furthermore, the employ of different excitation wavelengths allowed to distinguish the photoluminescence bands with both categories of devices, thus identifying rare earth elements (REEs) likely associated with the mineral's genesis. [ABSTRACT FROM AUTHOR]

The reliquary bust of Saint Lambert, hosted in the Treasure of the Liège Cathedral, was produced in the early 15th century. This exceptional goldsmithery piece is covered with gold‐coated silver, and decorated by approximately 400 stones, analysed by Raman and pXRF techniques to determine their mineralogical and chemical composition. The results confirm the identification of one hundred pearls, twenty‐six rock crystals, ten amethysts, two diamonds, and numerous glass beads with a green, blue, colourless, turquoise, orange or red colour. The glass beads show a soda‐lime composition, confirming that they are contemporary of the bust and imported from Venice, as reported by historical sources. Orange beads show a lead composition and the red stone a triplet with quartz, indicating that they were added to the bust later. The cutting of gems and beads shows also a significant evolution. The metal contains approximately 60% of Au and 40% of Ag. The origin of gemstones was difficult to establish, due to the absence of characteristic trace elements, but the chemical elements used for the manufacture and colouring of the beads were determined. This study confirms the trade of stones between Liège and Venice during medieval times. [ABSTRACT FROM AUTHOR]

The hazard, showing the long-term probability related to lava flow inundation, was obtained by combining three different kinds of information: the spatiotemporal probability of the future opening of new flank eruptive vents, the event probability associated with classes of expected eruptions and the overlapping of lava flow paths simulated by the MAGFLOW model. The resulting risk map shows the likely damage caused by a lava flow eruption, allowing rapid visualization of the areas in which there would be the greatest losses if a flank eruption occurred on Mt Etna. By combining the location of the main population centres on Etna with those where the hazard is high, the south-eastern flank is identified as the sector with the highest overall level of risk due to effusive eruptions from vents located on the volcano flanks. During most of the eruption, Bogoslof's vent was submerged in shallow seawater, although a subaerial edifice grew during more prolonged stages of the eruption, resulting in the vent becoming above sea-level with more ash-rich volcanic clouds. [Extracted from the article]

Few people have heard of the mineral sphene (also called titanite), but it is nevertheless extremely widespread, occurring in most common rocks. It can be useful to the Earth scientist as it contains information on the timing, temperature and pressure of formation of many common rocks. It is also a source of titanium—and can sometimes be used as a gemstone. [ABSTRACT FROM AUTHOR]

Here, we document a detailed characterisation of two zircon gemstones, GZ7 and GZ8. Both stones had the same mass at 19.2 carats (3.84 g) each; both came from placer deposits in the Ratnapura district, Sri Lanka. The U‐Pb data are in both cases concordant within the uncertainties of decay constants and yield weighted mean 206Pb/238U ages (95% confidence uncertainty) of 530.26 Ma ± 0.05 Ma (GZ7) and 543.92 Ma ± 0.06 Ma (GZ8). Neither GZ7 nor GZ8 have been subjected to any gem enhancement by heating. Structure‐related parameters correspond well with the calculated alpha doses of 1.48 × 1018 g−1 (GZ7) and 2.53 × 1018 g−1 (GZ8), respectively, and the (U‐Th)/He ages of 438 Ma ± 3 Ma (2s) for GZ7 and 426 Ma ± 9 Ma (2s) for GZ8 are typical of unheated zircon from Sri Lanka. The mean U mass fractions are 680 μg g−1 (GZ7) and 1305 μg g−1 (GZ8). The two zircon samples are proposed as reference materials for SIMS (secondary ion mass spectrometry) U‐Pb geochronology. In addition, GZ7 (Ti mass fractions 25.08 μg g−1 ± 0.18 μg g−1; 95% confidence uncertainty) may prove useful as reference material for Ti‐in‐zircon temperature estimates. Key Points: We document a detailed characterisation of the Sri Lankan zircon gemstones GZ7 and GZ8 and propose them as SIMS U‐Pb reference materials. Both specimens have high mean U mass fractions and concordant Cambrian (GZ7) and Ediacaran (GZ8) U‐Pb ages. In addition, GZ7 is proposed as a reference material for Ti‐in‐zircon temperature estimates. [ABSTRACT FROM AUTHOR]

Abstract: Lithium is used in a variety of everyday objects. The most important field of application is as components of battery electrolytes and electrodes. Next to salar brines, commercial lithium production relies on mineral ore sources such as spodumene, petalite, and lepidolite. This study provides an economic comparison of two processes for the extraction of lithium from zinnwaldite concentrate, a lithium mineral that can be found along the Czech/German border at Cínovec/Zinnwald. In contrast to the state‐of‐the‐art lithium extraction from siliceous ores, which is a hydrometallurgical extraction process with sulfuric acid, the novel direct‐carbonation process is based on digestion using supercritical carbon dioxide. An assessment of the capital and operating expenditures was also carried out. [ABSTRACT FROM AUTHOR]

The Dalijigetang syenogranite in the eastern section of the Eastern Kunlun Orogen (EKO), China, is rich in SiO2 and alkali elements, has high FeOT/MgO ratios and is strongly depleted in CaO and MgO. Chondrite-normalized REE patterns show light REEs enrichment, heavy REEs depletion and negative Eu anomalies (δEu = 0.43-0.53). The 104Ga/Al values range from 2.69 to 10.31. The combined total concentrations of Zr, Nb, Ce and Y (mean = 420.04 ppm) indicate that the Dalijigetang syenogranite is an A-type granite. The zircon εHf( t) values relatively are all moderately negative (−6.1 to −10.7), and the model ages ( tDM2) range from 1666 to 1960 Ma (mean = 1801 Ma), which is much older than zircon U-Pb ages (259 Ma). Based on integrated isotopic and geochemical data, we infer that the syenogranite formed by the partial melting of lower crustal material under low-pressure and high-temperature conditions. Based on the above data, combined with the regional geological background, we conclude that the Dalijigetang A-type syenogranite formed during an end-early Permian period of extension between two episodic subduction events within the EKO. This suggests that the onset of northward subduction of the Palaeo-Tethyan Ocean plate might have commenced as early as the early Permian. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Combining supercell models and hybrid B3PW exchangecorrelation functionals, ab initio simulations on quasi-stable configurations of interstitial O-i ions in α-Al2O3 (corundum) crystals and possible migration trajectories have been modelled. We have studied crystalline distortion around migrating O-i including interatomic distances and the effective atomic charges, as well as redistributions of the electronic density. Unlike neutral interstitial atom O-i studied by us previously, migrating Oi ion does not form dumbbells with the nearest regular O-qreg oxygen ions, due to the strong Coulomb interaction with the nearest Al+qreg cations as well as stronger repulsion between - Oi and adjacent regular O-qreg ions. We have also estimated the energy barrier for migration between the nearest quasi-stable configurations of interstitial O-i ion. One of these configurations is an octahedron formed by six nearest O-qreg anions in the centre of which O-i ion is located, unlike a neutral Oi atom which prefers to migrate directly towards one of adjacent O-qreg anions with the dumbbell formation. As the result, the barrier for O-i ion migration in corundum has been found to be by ∼70% smaller than that of Oi atom. [ABSTRACT FROM AUTHOR]

A group of 18 cameos dated from the 16th to 19th centuries (bearing motifs of Roman emperors and female members of their families) from the Constantine Schmidt-Ciążyński collection was investigated with gemmological analyses, supported by non-destructive mineralogical methods such as X-ray diffraction (XRD) and micro-Raman spectroscopy (RS) to ascertain the material used. Although there is no scientific method to date the specimens precisely, the mineralogical data supported by archaeological analyses enabled the estimation of the possible timing of the manufacture of the gems. As a result, the cameos were divided into four basic chronological groups: (1) Renaissance, (2) Baroque, (3) uncertain and (4) Classical and Neoclassical. [ABSTRACT FROM AUTHOR]

In this work, we studied coloured and colourless glass used as gems in Visigothic buckles possibly originating from the necropolises of Torredonjimeno, Duraton or Castilltierra in Spain. Scanning electron microscopy ( SEM) with energy-dispersive analysis ( EDS) and observations made with an optical microscope in reflected and transmission mode were performed in order to establish the composition, origin of the colour and decay process of these glass pieces. The chemical analysis of ancient glass can provide relevant information regarding the manufacturing approach used during a specific period. The results revealed the presence of various transition metal elements used as chromophore elements, as well as some metallic backing foils used to improve the colour of pieces of almost colourless glass. [ABSTRACT FROM AUTHOR]

The article states about the book Emerald City: The birth and evolution of an Indian Gemstone Industry by Lawrence A. Babb. Lawrence Babb, an anthropologist and historian worked extensively on the study of colored-gemstone trade in Jaipur and showed how Jain ideology led to the business prowess of the community. This book is of great interest to students, scholars and people of Jain community who study the material culture of South Asia.