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It is essential to have happiness in life and if this happiness is due to everything related to us, then it becomes even more vital for us. We all humans do not want to see our happiness ever going away from us, no matter how much money has to be spent on it. According to the survey, many people in our society still believe in gemology and astrology and this research paper is more helpful for such types of people who are very curious to wear gems to get rid of problems in their life on their finger. The objective of this research paper is to provide the optimal solution to society for self-recognizing the gemstone itself by their live camera so they can know where it has to be worn. The proposed model is based on a deep neural network, the YOLO v5 model, which can identify the gemstone based on automatic feature extraction within a fraction of a second. The proposed model is 99% confident and ready to predict the relevant finger and its hand to wear the detected gemstone. It is hoped that this research will be successful in removing the problems related to identifying the gemstones for middle-class people and will prevent people from going to a gemologist every day. [ABSTRACT FROM AUTHOR]

Brittle materials such as ceramics, glasses and oxide single crystals find increasing applications in advanced micro-engineering products. Machining small features in such materials represents a manufacturing challenge. Ultrasonic drilling constitutes a promising technique for realizing simple micro-holes of high diameter-to-depth ratio. The process involves impacting abrasive particles in suspension in a liquid slurry between tool and work piece. Among the process performance criteria, the drilling time (productivity) is one of the most important quantities to evaluate the suitability of the process for industrial applications. This paper summarizes recent results pertaining to the ultrasonic micro-drilling process obtained with a semi-industrial 3-axis machine. The workpiece is vibrated at 40 kHz frequency with an amplitude of several micrometers. A voice-coil actuator and a control loop based on the drilling force impose the tool feed. In addition, the tool is rotated at a prescribed speed to improve the drilling speed as well as the hole geometry. Typically, a WC wire serves as tool to bore 200 μm diameter micro-holes of 300 to 1,000 μm depth in glass and ruby. The abrasive slurry contains B4C particles of 1 μm to 5 μm diameter in various concentrations. This paper discusses, on the basis of the experimental results, the influence of several parameters on the drilling time. First, the results show that the control strategy based on the drilling force allows to reach higher feed rates (avoiding tool breakage). Typically, a 8 um/s feed rate is achieved with glass and 0.9 μm/s with ruby. Tool rotation, even for values as low as 50 rpm, increases productivity and improves holes geometry. Drilling with 1 μm and 5 μm B4C particles yields similar productivity results. Our future research will focus on using the presented results to develop a model that can serve to optimize the process for different applications. [ABSTRACT FROM AUTHOR]

This paper presents geology aspects of jeweler demantoid new manifestation, which was recently discovered in the Polar Urals. The mineralogical characteristics of the manifestation are described, demantoids chemical analysis results are shown, and comparative analysis of demantoids with samples from classical Ural deposits is given. The crystal chemical characteristics of demantoids from this manifestation are studied and color origin of these garnets is investigated. Demantoid mineralization is presented in two types: single rounded grains and granular discharges from 2 to 5 mm, which form small chains up to 1-2 cm; edges of the garnet. The garnet purity is low; there are numerous inclusions of tremolite, gas-liquid inclusions, hollow channels and cracks. Crystals are categorized as cleanliness 2. The presence of byssolite is the most characteristic sign for demantoids under study (the “horse tail” inclusion). The nature of byssolite distribution, morphology of its aggregates allows us to talk about several types: clustered secretions; needle inclusions; matted-fibrous aggregates. The Skalny manifestation is confined to the western endocontact of the ultra-massif Cyum-Keu massif and is represented by veins zone, in which there are numerous veins of jadeite, albite-jadeite and plagioclase-jadeite bodies. The host rocks for garnets are serpentized ultrabasic rocks. Aggregates are found in cracks (rupture) which filled by tremolite. Demantoids comparative analysis of the Skalny manifestation and famous Ural field the Novo-Karkodinskoe deposits (Middle Urals) with following comparison criteria were used: geology, deposit, structure of veins, morphology, gemological characteristics. Garnet mineralization was studied in the Skalny manifestation and garnet group mineralogical series was established: andradite, demantoid, topazolite and uvarovite. Together with garnet, talc, antigorite, tremolite and chromite are found. The noble varieties of andradite (topazolite, demantoid) can be used as a material for obtaining gemstones of average quality. [ABSTRACT FROM AUTHOR]

The paper considers a problem of gemstones valuation, based on real data. The main goal includes constructing a model that determines the evaluated price of a given stone on the basis of its description, expressed as a set of input variables values. A classic approach, utilising a multiple linear regression tool, is compared with nonlinear multilayer perceptrons. As the dataset contains a number of qualitative variables (e.g. gemstone colour purity, the clarity of the structure and a symbol of the certifying authority), the important part of solving the problem is selecting and implementing a proper method of encoding qualitative variables in a numeric form that is accepted by statistical and neural tools. The adoption of method for numerical representation of qualitative information is primarily determined by the scale of measurement for a given variable. In the research presented here, some classic encoding methods have been considered: for nominal variables - "one out of N", "equilateral coding", and representation based on a single numerical variable; for variables expressed on an ordinal scale, additionally selected variants of so called thermometric methods can be implemented. A number of experiments, with the use of Statistica software packet, have been made, and their results have been presented and discussed. Conclusions show generally higher effectiveness of neural networks over the multiple linear regression in the considered issue, but also significant indications concerning qualitative data preprocessing (encoding them in a numeric form) for valuation models have been introduced. [ABSTRACT FROM AUTHOR]

Jasper and agat mines have been recognized in the Soltanieh, about 56 km of north-eastern of Qom city and about 80 km of Tehran. Geologically, this region locates in Structural zonation of central Iran and Orumieh- Dokhtar volcanic belt, and that field had been studied, and there is (showing) evidence of precious stones and expensive mineral in the original of volcanic rocks of Orumieh- Dokhtar area. In the scattered outcrops of volcanic masses and sedimentary deposits of this rocks would be recognizable variety of valuable precious minerals. Regarding providing of geological maps in the scale of 1/2500 and gathering sample of minerals stones and sediments, it had been identified proportional concentration of jasper and agat in the five parts of this area. Economical potential had been confirmed to do different trace cutting and sections in these parts and preparatory extracting to open top, and it is estimated about 2500 tons of storage and possibility of extracting about 150 tones. In this paper has been tried to compare original of making above volcanic rocks to other part of Orumieh- Dokhtar belt toward north western to south eastern that would be included vast parts of Iran geology, it would be introduced other hopeful regions in southern parts. [ABSTRACT FROM AUTHOR]

Gemstones inspired people since the very beginnings of humankind due to their esthetic nature and as a symbol of lasting value and social superiority. Precious and decorative stones from the East Kazakhstan Region are known in this area of Central Asia since the early prehistory. The most precious among the Kazakhstan gemstones - emeralds - were processed by the factories in the Urals in the 16th-19th Centuries. Among other well-known non-metallic minerals there are sapphires, topazes and tourmalines, mostly occurring in the NE part of the territory. Local agates and chalcedony are largely represented by hand-made articles. There are also varieties of high-quality quartz and many other kinds of decorative stones, including the famous Altai jasper. The traditional position of local gemstones has changed with their modern application in science and technology. On contrary, demands for the local natural stones and their use for jewelry and artistic goods/souvenirs has dropped sharply due to the increasing introduction of synthetic stones to the World markets and their mass-scale and cheap production. Yet, the traditionally most precious gemstones have been stable in the people's value ranking, also as a form of a financial investment. Comparing to other countries, the East Kazakhstan precious stone deposits are still poorly known and only locally exploited. The national industrial application of the Kazakhstan hardest minerals is multi-facetted. Diamonds are widely used for cutting and polishing of other hard materials; rubies and sapphires are largely synthetic and applied in high-precision medical and other technical instruments. Quartz from the Altai region is employed in high-tech implements in radioindustry, optics, etc. Finally, varieties of agates and chalcedonies are used in production of detail parts of electronic precision balances and other measurement tools. Yet, for a genuine art and jewelry, the precious stones still remain as the basic, irreplaceable and eternal material in which achievements of human inspiration are permanently retained. In spite of the immense mineral riches, the East Kazakhstan gemstones industry is still largely limited to small-scale and almost exclusively locally operating mining activities. The major natural potential of precious non-metallic minerals justifies new prospection activities for the gemstone-hosting mineral ore deposits that are currently carried out, promising a revival of the once flourishing Central Asian gemstone trade and economy. The paper provides a short overview of (semi-) precious and decorative non-metallic minerals of the East Kazakhstan provenance and their future exploration in terms of their predictive depositional ore distribution and industrial applications. [ABSTRACT FROM AUTHOR]

Detrital zircon analysis has excellent potential to elucidate the evolution of the Rio Grande rift Chama fluvial system by characterizing the provenance of sediment and assessing fluvial connectivity of Rio Grande rift basins through time. This study uses U-Pb geochronology of detrital zircon separated from modern river sediment, terrace deposits with the Lava Creek B ash (640 ka), and three intermediate terraces to reconstruct the provenance of sediment carried by the Rio Grande rift Chama fluvial system over the last 640 ka. U-Pb detrital zircon ages for Red River sediment are further supported by high precision 40Ar/39Ar detrital sanidine dating, which has the ability to identify age populations that are not resolved by lower precision detrital zircon dates. The detrital zircon age spectra of a 640 ka Rio Grande terrace in the Albuquerque Basin and a 640 ka Rio Chama terrace show a number of diagnostic age peaks: 1) 23-25 Ma characteristic of the Latir Volcanic Field, 2) 27-28 Ma that could be either from the Latir or San Juan Volcanic Fields, 3) 34-35 Ma characteristic of the San Juan Volcanic Field, 4) Cretaceous-aged peaks, and 5) a "triple peak" consisting of 1.7, 1.4, and 1.1 Ga zircon derived from Precambrian basement, which is common in Phanerozoic sediments throughout the western U.S. Based on two samples, we interpret relatively abundant 28-36 Ma zircon in river sediment to be characteristic of the Rio Chama. These similarities are compatible with models showing that the Rio Chama - with San Juan Mountain headwaters - dominated the river system at 640 ka. Similar 28-35 Ma zircon in a 250-350 ka Rio Grande terrace in the Española Basin is compatible with models positing a San Juan Mountain source of detritus for the Rio Grande after spillover of Lake Alamosa ~430 ka, and with reworking of Santa Fe Group sediment. The 27-28 Ma temporal overlap between the San Juan and Latir Volcanic Fields is problematic for provenance, but modern river sand samples suggest it is possible to distinguish the 28 Ma San Juan Volcanic Field (Fish Canyon Tuff) zircon peak from the 22-27 Ma Latir Volcanic Field zircon peak. Although the Latir Volcanic Field has a 28.2 Ma tuff (Tetilla Peak Tuff), its associated zircon is much less abundant than younger zircon (e.g., the 25.49 Ma Amalia Tuff). The similar pattern of age peaks between 640 ka fluvial sediment in the Albuquerque Basin and the Rio Chama indicates that the Rio Chama dominated the river system at 640 ka. Preliminary detrital sanidine data for Red River sediment that was derived from the Latir Volcanic Field show that 23-25 Ma sanidine is twice as abundant as 27-29 Ma sanidine, and therefore abundant 27-29 Ma zircon in the Rio Grande system is interpreted to indicate fluvial connectivity to the San Juan Mountains. [ABSTRACT FROM AUTHOR]

This work examines the development, implementation, and impact of Provenance Proof, a blockchain platform developed for marginalized members of the artisanal gemstone mining industry. We explore the origin and motivation of the program, its growth and impact, and the challenges that continue to hinder its mission. Using an interpretive qualitative methodology, we make use of data from artisanal miners, NGOs, blockchain technology firms, jewelry designers, retailers, and others in the form of interviews, media, websites, presentations, and gemstone conferences. We find that despite strong funding and technical development, sustained usage among artisanal miners remains low. We identify both positive steps and challenges to successful and sustained deployment and augment the macro-level Framework of Blockchain-Supported Development. [ABSTRACT FROM AUTHOR]

A large group of commercial minerals known as “industrial minerals” is used worldwide. Industrial minerals are understood as useful mineral deposits, i.e. all minerals extracted from the earth, except for energy raw materials, metals, water and gemstones, and used for industrial purposes owing to their physical, chemical and mechanical properties. The geological structure of the continental eastern Fennoscandian Shield (Karelian Region), the basement of the East European Platform, is controlled by its long geological evolution from 3.5 Ga to the present. The extraction and use of mineral resources in what is now Russian Karelia began in the Old Russian state founded in the 9th century, when large-scale mica production was launched followed by salt production in salt works on the White Sea shore. The late 18th century saw the production of Tivdian-Belogorsk and Ruskeala marbles, Olonets gabbrodiabase, Shoksha crimson quartzite and Serdobol granite in stone quarries. The first attempts to study shungite were made in the 19th century. Long-term studies of Karelia’s industrial minerals have shown that Karelia’s mineral potential comprises a variety of essential multi-purpose industrial minerals such as diamond, graphite, shungite, kyanite, garnet, fluorite, quartz, pegmatitic and magmatic feldspar, muscovite, talc, alkaline asbestos and others. Of great importance are Precambrian dimension stone and crushed stone used in civil engineering. It is important to update technological methods for optimum processing of priority industrial minerals such as graphite, kyanite, fluorite, high-purity quartz, soapstone and shungite rocks. Dimension stone and aggregate stone production has a good outlook for the future comparing Karelian resources with a similar one in Finland. [ABSTRACT FROM AUTHOR]

Handicraft occupation is a strenuous job, often performed in poor work settings. Working in such conditions for a long period of time may lead to musculoskeletal pain in different body regions. The study aimed to evaluate the prevalence of lower back pain and their associated work-related psychosocial risk factors among the male handicraft workers in India. A self-reported questionnaire study was conducted among 286 male handicraft workers, including gemstone cutters, metalcraft workers, and miniature painters. The lower back pain was found to be the most prevalent (75.18%) and severe work-related health problem in this occupational group. Work-related psychosocial factors such as high job demand and low job control showed a significant association with the development of lower back pain. The findings suggested that despite the substantial impact of the physical work with respect to the etiology of musculoskeletal pain, researchers should expand their focus to work-related psychosocial issues. Preventive intervention strategies ensuring ergonomic workload and flexibility at the workplace of handicraft workers are highly recommended. [ABSTRACT FROM AUTHOR]

In this study, wear performance of diamond sawblades in sawing of rocks was experimentally investigated. Specific wear (SW) was selected as the criteria for sawblade wear performance and the SW was correlated with the rock physico-mechnical properties. Surface morphologies of wearing segments were also examined using scanning electron microscope (SEM) images. As a result, the microhardness was determined as the dominant physico-mechanical rock properties affecting the SW. Additionally; emerging, fractured, polished and pull-out crystals were observed in the wearing surfaces of the diamond segments. [ABSTRACT FROM AUTHOR]

Experiments on the condensation of steam jet submerged in the subcooled water were carried out. The water temperature and the inlet steam pressure were in the range of 293 K–343 K and 0.2–0.6 MPa, respectively. Four essential shapes of steam plume were enumerated. According to the comparisons of the pictures of steam plume with the graphs in the same size, the pressure came to maximum value in the contraction spots, except for the double expansion-emanative shape. Moreover, pressure distributions of the flow field were characterized by means of drawing isobar. Comparison and discussions on the relationship between steam plume and pressure distributions were given. With the increase of temperature, pressure distributions within steam plume became more complex. Radial pressure distributions were classified according to different regions. Comparisons of the pressure distributions at different water temperature and inlet steam pressure were obtained. [ABSTRACT FROM AUTHOR]

The extreme materials properties of diamond lend it to a range of semiconductor applications, but the difficulty in forming n-type diamond, and the unintentional inclusion of deleterious impurities has proved problematic. Co-doping diamond with boron and deuterium yields n-type conduction and recent theory suggests that BD2 and BD3 complexes have shallow donor levels. We show here that the proposed structures are unstable and structural relaxation result in deep levels or passive defects. We also comment on other proposed co-doping schemes: N-H-N, S-H and Si4-N. Finally we show that combination of theory and the polarized uptake of Ni in diamond contradict the current interstitial Ni models for the 1.404 eV center. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]