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Characterizing the Provenance Signatures and Geochemical Behaviors of Turquoise in Copper Deposits:Comparative Case Studies of Meiduk,Iran,and Tongling,China
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作者 Bahareh Shirdam Mingxing Yang +2 位作者 Jia Liu Ling Liu Andy Hsitien Shen 《宝石和宝石学杂志(中英文)》 CAS 2024年第S01期71-73,共3页
Turquoise, a hydrous phosphate of copper and aluminum, is highly valued for its unique colour and historical significance. The similarity in colour, quality, and pattern between turquoises from different localities ma... Turquoise, a hydrous phosphate of copper and aluminum, is highly valued for its unique colour and historical significance. The similarity in colour, quality, and pattern between turquoises from different localities may lead to confusion in determining their origins. This is particularly evident in the case of turquoises from Meiduk in Iran and Tongling in China(Fig.1).In Iran, turquoise deposits are typically associated with magmatic zones, specifically in the Meiduk mine, located 85 kilometers northwest of the Sar Cheshmeh porphyry copper deposit in Kerman Province. The deposit is hosted by Eocene volcanic rocks of andesitic-basaltic composition with porphyry-type mineralization associated with two Miocene calc-alkaline intrusive phases. Five distinct zones of the hypogene alteration include potassic, potassic-phyllic, phyllic, and propylitic zones, which are rich in magnetite. Mineralization processes include stockwork, dissemination, veinlets, and veins rich in garnet, chalcopyrite, magnetite, and anhydrite. Turquoise is found in transitional, leached, and supergene zones, primarily as fracture and seam fillers. In contrast, Chinese turquoises are more often found in sedimentary rocks, with significant exceptions in places like the Tongling mine in Anhui Province, which are hosted within magmatic rocks. The turquoise from Tongling is found in the Tongling area within the Middle-lower Yangtze Metallogenic Belt, an area characterized by complex tectonics and intense magmatic and metallogenic activities. The turquoise deposits are associated with iron-copper polymetallic mineralization within Early Cretaceous volcanic rocks.The turquoise from Meiduk exhibited a specific gravity range of 2.22 g/cm^(3)to 2.71 g/cm^(3), SWUV fluorescence from none to medium, and LWUV fluorescence from faint to strong, indicating diverse mineralogical compositions. SEM examination of turquoise from Meiduk reveals a variety of mineral morphologies. The turquoise displays closely packed arrays of elongated needle-like crystals, measuring 2 μm to 9 μm in length and 0.1 μm to 0.4 μm in thickness, indicating a dynamic growth environment. The density and alignment of these crystals suggest the space-constrained setting, likely influenced by rapid deposition from mineral-laden fluids, with crystals interlocked due to simultaneous nucleation events. Some crystals appear similarly elongated but are more dispersed, with greater separation between individual crystals. In other areas, the elongated turquoise crystals are tightly intergrown, creating a dense textural appearance, pointing to a stage where growth space became limited, resulting in an interlocking matrix. Additionally, some crystals radiate outward from a central point, forming a spherical pattern reaching about 18 μm. The turquoise from Tongling show a specific gravity range of 2.26 g/cm^(3)to 2.60 g/cm^(3), with consistent medium SWUV fluorescence and strong LWUV fluorescence. SEM examination reveals needle structures, plate-like structures, and spheroidal aggregates composed of needle and plate-like microcrystals. These spherical aggregates, some with diameters around 26 μm, exhibit the concentric growth structure covered by turquoise microcrystals, with crystal lengths of 8 μm. The surface needle-like microcrystals vary in size, approximately 3 μm in length, 2 μm in width, and 0.2 to 0.6 μm in thickness.Optical microscopy, Raman and FTIR spectroscopy reported the presence of quartz, gypsum, iron oxides such as jarosite and goethite, biotite, sericite, pyrite, galena, bornite, graphene oxide, malachite, and azurite as major associated minerals of Meiduk's. In contrast, the Tongling mine features minerals such as quartz, anatase, barite, sodium feldspar, illite, and malachite.Through EPMA and LA-ICP-MS results, the turquoises of Tongling exhibit similar average iron content(1.28% and 1.26% respectively), but significant differences in copper content. The turquoises of Meiduk have the average copper content of 6.97%, whereas Tongling samples show the higher content of 11.38%. Na, K, and Ca concentrations are also higher in Meiduk samples, suggesting interaction with alkali-rich fluids and potassic alteration. Trace elements such as Ti, Cr, Zn, Se, and Mo serve as tracing agents for Meiduk samples, while Be and W are associated with Tongling samples. Regarding rare earth elements(REEs), Meiduk samples show diverse δCe(0.14-4.62) and δEu(0.65-15.78) values, indicating a wide range of oxidation states and europium anomalies. The significant variability in LREE/HREE ratios(0.39-31.74) and ΣREE concentrations(0.25-240.72 ppm) suggests heterogeneous REE fractionation patterns. In contrast, Tongling samples display δCe(0.070-2.51) and δEu(0.238-4.87) ranges, with more consistent LREE/HREE ratios(0.128-10.2) and ΣREE values(0.069-4.08 ppm), indicating stable REE fractionation dynamics.This comparative study of turquoises from the Meiduk mine in Iran and the Tongling mine in China reveals significant similarities and differences in their geochemical and mineralogical characteristics. Both deposits are hosted within magmatic rocks and produce turquoise as a byproduct in open-pit copper mining operations, exhibiting comparable colors, patterns, and morphologies. However, distinct differences are noted in their mineral compositions and trace elements, with turquoise from Meiduk associated with a complex hydrothermal system rich in various sulfide and oxide minerals and higher copper, Na, K, and Ca concentrations, indicating alkali-rich fluid interactions. In contrast, the turquoise from Tongling, influenced by both volcanic and sedimentary processes, shows a higher copper content, presence of barite, and different trace elements such as Be and W. The REE patterns also highlight the contrasting geological histories and environmental conditions at each site, with Meiduk samples showing a broader range of oxidation states and europium anomalies compared to the more stable REE fractionation dynamics in Tongling samples. These differences underscore the importance of detailed geochemical and mineralogical analyses for accurate provenance determination in gemmological and archaeological contexts. 展开更多
关键词 turquoise copper mine origin determination Meiduk Iran Tongling China
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活性染料Turquoise Blue G染色布面品质的控制方法 被引量:1
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作者 孙军 王思捷 《轻纺工业与技术》 2011年第4期38-40,共3页
Reactive Turquoise Blue G是生产艳蓝、亮绿类色系棉产品的优选染料,但其分子结构大,溶解度小,直接性高,扩散性差,易造成染色不均和色花;染料分子与纤维键结合能力差,当加入高浓度的促染盐后,易发生盐析现象,在布面产生色斑。现重点探... Reactive Turquoise Blue G是生产艳蓝、亮绿类色系棉产品的优选染料,但其分子结构大,溶解度小,直接性高,扩散性差,易造成染色不均和色花;染料分子与纤维键结合能力差,当加入高浓度的促染盐后,易发生盐析现象,在布面产生色斑。现重点探讨了Turquoise Blue G在棉产品生产中的色斑和色花的解决方法。 展开更多
关键词 色花 色斑 盐析 turquoise BLUE G
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Cascate del Mulino:Tuscany's natural wonderland
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作者 郑玉峰 《疯狂英语(新读写)》 2025年第3期12-14,74,共4页
Among the rolling hills and vineyards of the Tuscan countryside lies one of the most impressive tourist attractions not only in Italy,but in the entire world-a cascade(小瀑布)of white limestone pools overflowing with ... Among the rolling hills and vineyards of the Tuscan countryside lies one of the most impressive tourist attractions not only in Italy,but in the entire world-a cascade(小瀑布)of white limestone pools overflowing with warm turquoise(绿松石色)water known as Cascate del Mulino. 展开更多
关键词 cascate del mulino Cascades Tourist attraction white limestone pools White limestone pools Warm turquoise water
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Microinvasive analysis of textile relics from an ancient Silk Road turquoise mining site
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作者 XIAO Wei XIAN YiHeng +3 位作者 YU Chun WANG Yan SUN LiJuan LI YuFang 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2023年第8期2286-2296,共11页
The Xinjiang region,with its unique location and climate,exhibits well-preserved relics of great academic interest.This paper focuses on the microinvasive analysis of textile samples obtained from an ancient turquoise... The Xinjiang region,with its unique location and climate,exhibits well-preserved relics of great academic interest.This paper focuses on the microinvasive analysis of textile samples obtained from an ancient turquoise mining site in the Heishanling region of Xinjiang,active between 820 and 400 BC.Various analytical techniques,including optical microscopy,scanning electron microscopy,Fourier-transform infrared spectroscopy with attenuated total reflection,and liquid chromatography-mass spectrometry,were employed to investigate these textiles.The results revealed that the textiles were composed of wool and dyed using indigo and purpurin.The bluegrass and madder-derived dyes were likely sourced locally or imported from wetter regions such as the Chinese Central Plains.The infrared deconvolution spectra and the results demonstrated that red and blue dyes considerably influenced the movement of wool fiber chains,leading to a more rapid decay of dyed fibers compared to those that were undyed.In addition,the medium dyeing process and Ke techniques were employed to create unique color shades and special patterns.This scientific and technological analysis of the textiles provides essential data for elucidating the materials available to ancient laborers.Furthermore,it offers scientific evidence supporting the cultural exchange between the western regions and the Central Plains and integration along the Silk Road. 展开更多
关键词 microinvasive analysis textile relics turquoise mining site weave
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PERFORMANCE UNDER PRESSURE
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作者 Li Qing 《Beijing Review》 2025年第36期22-23,共2页
High-quality cookware makes life easier for families in Xizang,From an aerial view,Xizang Autonomous Region unfolds like a vast,breath-taking canvas.Snow-capped peaks glisten under the sun,turquoise lakes shimmer like... High-quality cookware makes life easier for families in Xizang,From an aerial view,Xizang Autonomous Region unfolds like a vast,breath-taking canvas.Snow-capped peaks glisten under the sun,turquoise lakes shimmer like scattered jewels,and endless grasslands stretch across what is known as the Roof of the World.Yet beneath this magnificent beauty lies a challenge that has shaped daily life in the region for generations. 展开更多
关键词 performance pressure xizang autonomous region roof world snow capped peaks endless grasslands turquoise lakes high quality cookware
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