Results 51 to 60 of about 1,047 (213)
Thermal Temperature Measurements of Plasma Torch by Alexandrite Effect Spectropyrometer
Advances in Optical Technologies, Volume 2010, Issue 1, 2010., 2010 An alexandrite effect spectropyrometer is used to directly measure the thermal temperature of an argon gas plasma jet from a 100 kW DC plasma torch, and the directly measured thermal temperature of the plasma is 11178 ± 382 K. By using the spectral correction function to delete the spectral lines and to correct its underlying spectrum of the relative ...
Peir-Jyh Wang +3 more
wiley +1 more source
Photochromism, UV-Vis, Vibrational and Fluorescence Spectroscopy of Differently Colored Hackmanite
Crystals, 2023 Because of the rich fluorescent color and unique photochromic properties, hackmanite has attracted many mineralogists. In this paper, the basic gemmological characteristics and photochromic and fluorescence mechanisms of four different colors of ...
Chuchu Song +4 more
doaj +1 more source
Journal of Raman Spectroscopy, Volume 56, Issue 11, Page 1235-1253, November 2025.This study presents the gemological analysis of 25 garnets from Hellenistic and Roman jewellery in the Archaeological Museum of Thessaloniki using mobile Raman spectroscopy and micro‐EDXRF. The garnets are classified into three geochemical clusters, with notable differences in distribution between Thessaloniki and Pydna, suggesting distinct trading ...
Maria Nikopoulou +8 more
wiley +1 more source
CrystalsThe Longido region (Tanzania) hosts a distinct corundum–zoisite paragenesis, renowned for its ornamental value and geological significance as a tracer of Pan-African tectonothermal events.
Ling Yang +4 more
doaj +1 more source
Crystals, 2023 The Chuncheon nephrite deposit in South Korea is one of the major nephrite deposits in the world, but its origin has been rarely studied. This study explores the mineralogical and geochemical characteristics of the Chuncheon nephrite using a polarizing ...
Nan Li, Feng Bai, Qi Peng, Mengsong Liu
doaj +1 more source
Field Gemology: Building a Research Collection and Understanding the Development of Gem Deposits
Gems & Gemology, 2019 GEMS & GEMOLOGY WINTER 2019 Over the last decade, GIA has invested considerable resources in determining the geographic origin of certain gemstones. The field gemology program plays an essential role in these studies.
W. Vertriest +2 more
semanticscholar +1 more source
The Pace di Siena and its Gems
Journal 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
Modeling the polychromism of oxide minerals: The case of alexandrite and cordierite
Journal of Computational Chemistry, Volume 45, Issue 12, Page 834-842, May 5, 2024.In this work, we tested the embedded cluster approach for the simulation of the polychromism of alexandrite and cordierite by TD‐DFT. The fitted point charge embedding allowed to reproduce both transition energies and anisotropy of absorption spectra at the origin of the polychromism of these minerals. The simulation was in qualitatively good agreement
Raphaël Rullan +4 more
wiley +1 more source
Gemological and Mineralogical Characteristics of Emerald from Ethiopia
Crystals, 2023 Ethiopia has been gaining attention in recent years as an emerging source of high-quality emerald. Ethiopian emerald samples with different colors ranging from dark green to light green were selected to study the gemological properties, chemical ...
Zixuan Huang +3 more
doaj +1 more source