Results 61 to 70 of about 15,039,014 (169)

Gemological and Spectral Characteristics of a New Type of Emerald Synthesized by the Hydrothermal Method

open access: yesYankuang ceshi, 2023
BACKGROUND The emerald is loved by people because of its gorgeous color and is respected as one of the world's four major gems. Due to the high value of emeralds, a variety of synthesis and optimization methods have emerged.
ZHU Hongwei   +8 more
doaj   +1 more source

Evaluation of the Color Changing of Flux‐Synthesized Beryl by Ni Doping Using CIE1976 Color Parameters

open access: yesEuropean Journal of Inorganic Chemistry, Volume 29, Issue 13, 1 May 2026.
Comprehensive quantitative analysis of the relationship between NiO concentration and CIE1976 color parameters in Ni‐beryl crystals. Rough beryl contains various transition metal species owing to its geological formation conditions, and their concentrations largely determine the resulting crystal's color—a key physical property that strongly influences
Yusei Sonobe   +15 more
wiley   +1 more source

Spectroscopic Characteristics of Treated‐Color Natural Diamonds

open access: yesJournal of Spectroscopy, Volume 2018, Issue 1, 2018., 2018
With the increasing availability of treated‐color diamonds on the market, their characterization is becoming more and more critical to the jewelry testers and customers. In this investigation, ten color diamonds treated by irradiation (4 pieces), HPHT (3 pieces), and multiprocess (3 pieces) were examined by spectroscopic methods.
Meili Wang   +5 more
wiley   +1 more source

The Pace di Siena and its Gems

open access: yesJournal of Raman Spectroscopy, Volume 56, Issue 11, Page 1254-1278, November 2025.
For the first time, the gems of the Pace di Siena, a rare en ronde bosse enamel preserved in Arezzo (Italy), have been analyzed using a transdisciplinary approach. The combination of gemmology and Raman spectroscopy has led to the identification of blue sapphires and pink spinels, contradicting previous historical classifications.
Stefania Martiniello   +6 more
wiley   +1 more source

Color Dependence on Thickness in Topaz Crystal from Brazil

open access: yesAdvances in Condensed Matter Physics, Volume 2012, Issue 1, 2012., 2012
It is well known that crystals of topaz from the Eastern Brazilian Pegmatite Province may turn blue by the irradiation with 60Co gamma rays followed by heat treatment. Also, it is known that the sensation of color changes with the thickness of these crystals. The dependence of the color, given by 1931 CIE chromaticity coordinates, with the thickness of
Waldemar Bonventi Jr   +3 more
wiley   +1 more source

Material Profiling of Mesopotamian Cylinder Seals by Raman Spectroscopy

open access: yesJournal of Raman Spectroscopy, Volume 56, Issue 3, Page 228-242, March 2025.
Mesopotamian cylinder seals (fourth ‐ first millennium bce) from the collection of Museum für Kunst und Gewerbe, Hamburg were non‐destructively studied by Raman spectroscopy were non‐destructively studied by Raman spectroscopy. The Raman spectral analysis identified the mineral constituents and quantitatively determined the chemical compositions of the
Stylianos Aspiotis   +5 more
wiley   +1 more source

A Machine Learning Approach to Single Garnet Geothermometry and Application to Tracing the Fingerprint of Superdeep Diamonds

open access: yesGeochemistry, Geophysics, Geosystems, Volume 26, Issue 3, March 2025.
Abstract Estimating the equilibration temperatures of mantle‐derived garnets is crucial for assessing the diamond potential of kimberlites. Traditional garnet geothermometers require co‐existing mineral data or costly trace element analysis, limiting their practical use.
Qiwei Zhang   +6 more
wiley   +1 more source

ND70 Series Basaltic Glass Reference Materials for Volatile Element (H2O, CO2, S, Cl, F) Measurement and the C Ionisation Efficiency Suppression Effect of Water in Silicate Glasses in SIMS

open access: yesGeostandards and Geoanalytical Research, Volume 48, Issue 3, Page 637-660, September 2024.
Key Points New set of widely available reference materials, for in situ measurement of volatile elements (H2O, CO2, S, Cl, F) in silicate glass of basaltic composition. Characterised using ERDA, NRA, EA, FTIR and EPMA, and SIMS on four different ion probes. SIMS CO2 measurement results are significantly influenced by the H2O content of the glass.
Yves Moussallam   +17 more
wiley   +1 more source

Mechanical Impact of Heterogeneously Distributed H2O on Quartz Deformation

open access: yesJournal of Geophysical Research: Solid Earth, Volume 129, Issue 8, August 2024.
Abstract In order to identify relations between mechanical behavior, deformation mechanisms, microstructural properties, and H2O distribution, Tana‐quartzite samples with added H2O ranging from 0 to 0.5 wt.% were deformed by axial shortening at constant displacement rates, at 900°C and 1 GPa, reaching up to ∼30% bulk strain.
Petar Pongrac   +9 more
wiley   +1 more source

Corroborating the autoptic identification of archeological glyptics in museum collections: The contribution of portable Raman spectroscopy

open access: yesJournal of Raman Spectroscopy, Volume 55, Issue 2, Page 200-215, February 2024.
A collection of Hellenistic–Roman glyptics was investigated in situ at the Regional Archaeological Museum “Paolo Orsi” (Syracuse, Italy), with portable Raman spectroscopy. 85% of the samples was successfully identified, the attribution was corrected for 4% of the gemstones, among which a gold ring with garnet, previously mistaken for carnelian.
Maria Cristina Caggiani   +5 more
wiley   +1 more source

Home - About - Disclaimer - Privacy