Academic Journal
Nephrite from Xinjiang Qiemo Margou Deposit: Gemological and Geochemical Insights
| العنوان: | Nephrite from Xinjiang Qiemo Margou Deposit: Gemological and Geochemical Insights |
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| المؤلفون: | Ting Fang, Yuan Chang, Mingxing Yang |
| المصدر: | Minerals, Vol 14, Iss 5, p 458 (2024) |
| بيانات النشر: | MDPI AG |
| سنة النشر: | 2024 |
| المجموعة: | Directory of Open Access Journals: DOAJ Articles |
| مصطلحات موضوعية: | nephrite, tremolite–actinolite, chemical composition, Mineralogy, QE351-399.2 |
| الوصف: | The nephrite belt in the Altun Mountain–Western Kunlun Mountain region, which extends about 1300 km in Xinjiang, NW China, is the largest nephrite deposit in the world. The Qiemo region in the Altun Mountains is a crucial nephrite-producing area in China, with demonstrated substantial prospects for future exploration. While existing research has extensively investigated secondary nephrite deposits in the Karakash River and native black nephrite deposits in Guangxi Dahua, a comprehensive investigation of black nephrite from original deposits in Xinjiang is lacking. Margou black-toned nephrite was recently found in primary deposits in Qiemo County, Xinjiang; this makes in-depth research on the characteristics of this mine necessary. A number of technical analytical methods such as polarizing microscopy, Ultra-Deep Three-Dimensional Microscope, electron microprobe, back-scattered electron image analysis, X-ray fluorescence, and inductively coupled plasma mass spectrometry were employed for this research. An experimental test was conducted to elucidate the chemical and mineralogical composition, further clarifying the genetic types of the black and black cyan nephrite from the Margou deposit in Qiemo, Xinjiang. The results reveal that the nephrite is mainly composed of tremolite–actinolite, characterized by Mg/(Mg + Fe 2+ ) ratios ranging from 0.86 to 1.0. Minor minerals include diopside, epidote, pargasite, apatite, zircon, pyrite, and magnetite. Bulk-rock rare earth element (REE) patterns exhibit distinctive features, such as negative Eu anomalies (δEu = 0.00–0.17), decreasing light REEs, a relatively flat distribution of heavy REEs, and low total REE concentrations (1.6–38.9 μg/g); furthermore, the Cr (6–21 μg/g) and Ni (2.5–4.5 μg/g) contents are remarkably low. The magmatic influence of granite appears to be a fundamental factor in the genesis of the magnesian skarn hosting Margou nephrite. The distinctive black and black cyan colors are attributed to heightened iron content, mainly associated with FeO ... |
| نوع الوثيقة: | article in journal/newspaper |
| اللغة: | English |
| Relation: | https://www.mdpi.com/2075-163X/14/5/458; https://doaj.org/toc/2075-163X; https://doaj.org/article/914100521c20426cb66f9bfa92044e9c |
| DOI: | 10.3390/min14050458 |
| الاتاحة: | https://doi.org/10.3390/min14050458 https://doaj.org/article/914100521c20426cb66f9bfa92044e9c |
| رقم الانضمام: | edsbas.EEE0DFEF |
| قاعدة البيانات: | BASE |
| DOI: | 10.3390/min14050458 |
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