Results 51 to 60 of about 15,039,014 (169)
Gemological characteristics and origin of basalt-related sapphire in Dong Nai province
Science and Technology Development Journal - Natural SciencesBasalt – related sapphire in Thong Nhat District, Dong Nai Province, Vietnam, are found in alkaline basalts and their lateritic weathering layers. This study employs standard gemological methods and advanced analytical techniques such as XRD, EDX, Raman ...
Le Ngoc Nang +4 more
semanticscholar +1 more source
Minerals, 2020 The Zhanguohong agate from Beipiao (Liaoning province, China), which occurs in the intermediate–felsic volcanic breccias of the Early Cretaceous Yixian Formation, generally shows massive and banded structures, with red, yellow, and/or white layers or ...
Xue-Mei Zhang, Lei Ji, Xue-Mei He
semanticscholar +1 more source
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
doaj +1 more source
CrystalsThe “yellow-skinned” Nanhong agate represents a unique variety of Nanhong agate found in northeastern Yunnan, China, and it is highly valued for its distinctive yellow exterior and clear red–yellow interface. Owing to the limited research on this variety,
Qiuyun Song +7 more
semanticscholar +1 more source
MineralsAfrica hosts numerous emerald deposits, among which Sumbawanga, located at the junction of Tanzania, Zambia, Congo, and Malawi, stands out as one of the significant localities.
Yi Guo, Xiao-Yan Yu, Chen-Xi Li
semanticscholar +1 more source
Gemological Characteristics and Coloration Mechanism of Vanadium-Bearing Beryl from Nigeria
MineralsVanadium-bearing beryl is a vanadium-bearing variety of green beryl (distinct from emerald) that exhibits an “electro-optical” green (blue-green) color, which has led to its commercial popularity.
Yu Hong +4 more
semanticscholar +1 more source
The Chemical Composition of Trapiche-like Quartz from Huanggangliang Area, Inner Mongolia, China
Crystals, 2022 Trapiche-like quartz, which is found in Huanggangliang area, Chifeng City, Inner Mongolia, China, has a short columnar euhedral shape. Arms of trapiche-like phenomena are formed by six radial dark bands located along the a-axis of crystals, and their ...
Ling Jiang, Zhu Chen, Yingxin Liu
doaj +1 more source
Geostandards and Geoanalytical Research, Volume 50, Issue 3, Page 677-700, September 2026.Key Points Low‐Mg calcite RM developed for in situ microanalysis applications in palaeoclimatology (δ18O, δ13C; Mg, Sr m/m). New data for calcite CRM IAEA‐603 (δ18O, δ13C by SIMS and GS‐IRMS; Mg m/m). No detectable IMF effect of Mg on SIMS δ18O determinations for mass fractions < 3650 μg g‐1.
Andreas T. Hertwig +13 more
wiley +1 more source
Visible and Near‐Infrared Reflectance Spectroscopy for Investigating Soil Mineralogy: A Review
Journal of Spectroscopy, Volume 2018, Issue 1, 2018., 2018 Clay minerals are the most reactive and important inorganic components in soils, but soil mineralogy classifies as a minor topic in soil sciences. Revisiting soil mineralogy has been gradually required. Clay minerals in soils are more complex and less well crystallized than those in sedimentary rocks, and thus, they display more complicated X‐ray ...
Qian Fang +6 more
wiley +1 more source
The Talisman of Charlemagne: New Historical and Gemological Discoveries
, 2019 The gem-bearing reliquary known as the Talisman of Charlemagne is closely associated with the history of Europe. Its legend follows such figures as Charlemagne, Napoleon I, Empress Josephine, Hortense de Beauharnais, Napoleon III, and Empress Eugénie ...
Krzemnicki, Michael +6 more
core +1 more source