Results 51 to 60 of about 265 (147)
Crystals, 2023 Ospinsk is an area in Russia well-known for mining the highest quality green nephrite in the world. However, the chatoyant green nephrite found here has not been studied to date.
Weishi He +4 more
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CrystalsThe Malysheva emerald mine (Urals, Russia) boasts a long history and extraordinary emerald output. However, recent studies indicate that Malysheva emeralds share highly similar inclusion varieties, UV-visible-near infrared (UV-Vis-NIR) spectra, and ...
Yu-Yu Zheng +3 more
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CrystalsSpodumene is a characteristic mineral in lithium-rich granitic pegmatites, serving both as a valuable mineral resource and an important gem material. This study incorporates three different color varieties of spodumene—pink to violet, yellow-green, and ...
Zijia Zhou +4 more
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CrystalsBiotite–phlogopite minerals are a complete Mg–Fe isomorphism series of phyllosilicates. A Fourier transform infrared spectroscopy (FTIR) and electron microprobe analysis (EMPA) were conducted on end-member phlogopite, Mg–biotite, and annite samples.
Zhentao Yang +4 more
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The Effect of Heat Treatment on Yellow-Green Beryl Color and Its Enhancement Mechanism
CrystalsBeryl is classified as a cyclosilicate mineral, and its color is primarily determined by the type and oxidation state of trace elements. In this study, natural yellow-green beryl was used as the research subject, and heat treatment experiments were ...
Binru Hao, Shuxin Zhao, Qingfeng Guo
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CrystalsPearl color serves as the paramount criterion for quality assessment and commercial valuation in the global pearl industry. Freshwater nucleated pearls, which constitute 95% of global production, exhibit striking chromatic diversity. This study deciphers
Baoyi Yang +5 more
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Gemological Characteristics and Trace Chemical Element Analysis of Emerald in Kafubu, Zambia
CrystalsThis study systematically analyzed the color characteristics, microscopic inclusions (including fluid and mineral inclusions), spectral properties, and chemical composition of emerald samples from Kafubu, Zambia using infrared spectroscopy, UV–visible ...
Yiwei Jiang +3 more
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CrystalsA new type of vesuvianite jade has recently been discovered in Hanzhong City, Shaanxi Province, China. However, a systematic investigation into its mineralogical characteristics and the origin of its color is currently lacking.
Ye Yuan +4 more
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The Characteristics of Luminescence from High-Temperature- and High-Pressure-Treated Diamonds
Applied SciencesHigh-temperature and high-pressure (HTHP)-treated diamonds have attracted attention all over the world due to their vivid colors. In order to explore a new method for the rapid and non-destructive identification of HTHP-treated diamonds, in this paper ...
Mu-Lin Huang +4 more
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