Results 41 to 50 of about 354 (163)

Yeşil opalin gemolojik özellikleri = Gemological characteristics of green opal [PDF]

, 2017
Bu çalışmada; İnceleme alanı, Türkiye’nin doğusunda bulunan Doğu Anadolu Bölgesi’nde Kırdağ’daki, Şenkaya (Erzurum) ilçesinin batı-kuzeybatısında yer alır. Türkiye’de ve Dünya’da gerçekten nadir rastlanan yeşil opal, koyu ve açık tonlarda elma veya fıstık yeşili renginde bir mineraloiddir.
Şahin, Ferhan
openaire   +1 more source

Cultured Pearls from Lake Kasumigaura: Production and Gemological Characteristics

Gems & Gemology, 2018
Ahmadjan Abduriyim
exaly   +2 more sources

Mineralogical and gemological characteristics of Kaman (Kırşehir-Türkiye) fluorites

Gümüşhane Üniversitesi Fen Bilimleri Enstitüsü Dergisi, 2022
Fluorites are found in the region between Hamit, Karakütük, Bayındır and Yeniyapan villages of the Kaman District (Kırşehir-Türkiye). Fluorites are located in altered levels due to faults in quartz syenites containing gray-pink colored K-feldspar, plagioclase and quartz, amphibole and biotite type mafic minerals in the Upper Cretaceous aged.
İlkay KAYDU AKBUDAK, Doğanay Elif KETENCİ, Meltem GÜRBÜZ   +2 more
openaire   +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
wiley   +1 more source

A Gemological and Spectroscopic Study with Mobile Instruments of “Emeralds” from the Coronation Crown of Napoleon III

, 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, Karampelas, Stefanos, Hennebois, Ugo, Delaunay, Aurélien, Sainte Beuve, Bérengère Meslin, Lechartier, Michel, Herreweghe, Annabelle, Leblan, Sophie, Nectoux, Didier, Gaillou, Eloïse   +9 more
core   +1 more source

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
wiley   +1 more source

Characterization of Blue Tourmaline from Madagascar for Exploring Its Color Origin

Advances in Condensed Matter Physics, Volume 2022, Issue 1, 2022., 2022
In the research, spectroscopic studies of tourmaline for color origin were performed by X‐ray diffraction, Fourier transform infrared spectroscopy, ultraviolet‐visible spectroscopy, and X‐ray photoelectron spectroscopy. The research work emphasized the analysis of transition metal atoms, including their valence state and coordination number, in order ...
Ming Li, Ram N. P. Choudhary
wiley   +1 more source

Coupling Mineralogy and Oxygen Isotopes to Seasonal Environmental Shifts Recorded in Modern Freshwater Pearl Nacre From Kentucky Lake

Geochemistry, Geophysics, Geosystems, Volume 22, Issue 12, December 2021., 2021
Abstract Biominerals that accrete shell or skeleton are commonly used as windows to past geochemical environments. Using biominerals as paleoproxies depends on the assumption that biominerals faithfully and predictably record environmental parameters, yet little has been done from a mineralogical perspective to understand how various environmental ...
G. A. Farfan, C. Zhou, J. W. Valley, I. J. Orland   +3 more
wiley   +1 more source

Influence of metamictization on the gemological properties of natural zircon: A Raman spectroscopic study of zircons in the gemological collection of Abraham Gottlob Werner

Journal of Raman Spectroscopy, Volume 52, Issue 1, Page 71-77, January 2021., 2021
Abstract Raman spectroscopy is a convenient, efficient, and non‐destructive technique that could estimate the metamictization degree of zircon, particularly for gem‐class or historical samples. The full width at half maximum value of the ν3(SiO4) band around 1000 cm−1 can classify the structural state of zircon as crystallized (the full width at half ...
Shijia Gao, Gerhard Heide
wiley   +1 more source