Results 31 to 40 of about 15,039,014 (169)
Известия высших учебных заведений: Геология и разведка, 2019 For the first time, data on the mineral composition and gemological characteristics of the jewelry-ornamental ammonites of the Republic of Adygea have been presented.
D. A. Petrochenkov
doaj +2 more sources
Известия высших учебных заведений: Геология и разведка, 2018 Fossils of marine reptiles are a new jewelry and ornamental material and collected in the Ulyanovsk region from the Upper Jurassic deposits. They consist of (wt. %): calcite — 52, apatite — 24 and pyrite — 23, and also gypsum presents.
D. A. Petrochenkov
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Crystals, 2023 The orange fluorescence of scapolite has been confirmed to be caused by (S2)−, but the frequent blue fluorescence in gem-quality scapolite has not been well explained.
Yinghua Rao +3 more
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Spectroscopic Characteristics and Coloring Mechanisms of Different Colored Spinels from Myanmar
Crystals, 2023 Spinel is a common gemstone that has attracted the attention of gemologists worldwide because of its high refractive index, rich colors and brilliant hues. Myanmar is an important source of spinel. The present paper provides a systematic characterization
Lei Zhang, Kui He, Qingfeng Guo
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The Gemological Collection of Abraham Gottlob Werner [PDF]
, 2021 The gemological collection of Abraham Gottlob Werner contains 1374 sample numbers for 25 different minerals with 38 gemological varieties, including 15 newly added numbers of samples, which were not recorded in the original catalog of 1823. In total, 168
Gao, Shijia
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Micron, 2023 In this study, we comparatively investigated the gemological and fine-microstructural characteristics of yellow seawater pearls cultured in Pinctada fucata martensii using X-ray computed microtomography (μ-CT) analysis, ultraviolet-visible (UV-Vis ...
Xu Yan +6 more
semanticscholar +1 more source
Diffusion of Hydroxylated Si Vacancies in Olivine, and Its Relevance to Si Diffusion
Geochemistry, Geophysics, Geosystems, Volume 24, Issue 5, May 2023., 2023 Abstract The diffusion coefficient associated with the 3,612 cm−1 infrared absorbance band in H‐bearing olivine, attributed to a defect involving a vacant Si site balanced by four H+ (i.e., ), was determined in H in‐diffusion experiments at 1200°C–1400°C and 1.5–3.0 GPa in piston‐cylinder and multi‐anvil apparatuses.
Michael C. Jollands
wiley +1 more source
Spectroscopic Study on the Species and Color Differences of Gem‐Quality Red Garnets from Malawi
Journal of Spectroscopy, Volume 2022, Issue 1, 2022., 2022 To reveal the species of gem‐grade red garnets with similar colors, especially the mechanisms underlying their subtle color differences, a series of tests, including conventional gemological tests, X‐ray diffraction, Fourier‐transform infrared spectroscopy, ultraviolet‐visible spectroscopy, and X‐ray photoelectron spectroscopy, were performed on gem ...
Ming Li, K. S. V. Krishna Rao
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Spectroscopic Characteristics and Color Origin of Red Tourmaline from Brazil
Journal of Spectroscopy, Volume 2022, Issue 1, 2022., 2022 In the present paper, I report on the spectroscopic study for tourmaline color origin, performed red samples from Minas Geras State, Brazil, by gemological routine testing, X‐ray diffraction, Fourier transform infrared spectroscopy, ultraviolet‐visible spectroscopy, and X‐ray photoelectron spectroscopy.
Ming Li, Davidson Sajan
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, 2022 International audienceForty-five “emeralds,” formerly set in the coronation crown of Napoleon III, were studied using nondestructive mobile spectroscopic and gemological means.
Maouche, Farida +9 more
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