辽宁抚顺和新疆吉木萨尔煤精的显微组成和拉曼光谱对比研究

Comparative Study on Maceral Composition and Raman Spectroscopy of Jet From Fushun City,Liaoning Province and Jimsar County,Xinjiang Province

煤精又称煤玉,是一种资源稀缺且价格昂贵的煤种,可作为工艺美术雕琢材料。采集了辽宁抚顺和新疆吉木萨尔这两个地区的6件煤精样品,测试分析了其煤岩煤质(显微组成、腐植体最大反射率、工业分析、元素分析)和拉曼光谱特征。研究结果表明6件煤精样品中显微组分均以腐植组为主,稳定组次之,惰质组含量最低,腐植体最大反射率(R_(o, max))介于0.41%~0.55%;抚顺煤精的稳定组以沥青质体和孢子体为主,而吉木萨尔煤精的稳定组则以角质体为主;这两个地区煤精的拉曼光谱特征差异显著,拉曼结构参数显著受控于煤岩煤质;煤精的拉曼光谱参数D_(1)峰与G峰的强度比(I_(D_(1))/I_(G))、面积比(A_(D_(1))/A_(G))均随稳定组含量增加而显著增大,随腐植组和惰质组含量的增加而明显减小;吉木萨尔煤精的I_(D_(1))/I_(G)和A_(D_(1))/A_(G)值均显著小于抚顺煤精,这是由于抚顺煤精中含有大量沥青质体和孢子体,其大分子结构的芳环生长程度较差;这两个地区煤精的I_(D_(1))/I_(G)和A_(D_(1))/A_(G)值均随着R_(o, max)增大呈现差异化降低趋势;随着煤化程度增大,芳香层片空间排列有序化增强。拉曼光谱参数可有效指示不同产地煤精的大分子结构差异性,可为今后煤精类文物的产地溯源提供科学依据,进而为了解中国古代手工业发展史及商品流通提供启示。

Jet,also known as coal jade,is a type of coal with scarce resources and high costs,and it can be used as a material for art and craft carvings.Six jet samples were collected from Fushun City,Liaoning Province and Jimsar County,Xinjiang Autonomous Region,to analyse their petrographic properties and quality(i.e.,maceral composition,maximum huminite reflectance,proximate analysis,and ultimate analysis)as well as Raman spectroscopic characteristics.The results showed that the macerals of the six jet samples are composed of mainly huminite,followed by liptinite,and then inertinite with a shallow content;moreover,the maximum huminite reflectance(R_(o, max))is observed to be 0.41%~0.55%.The liptinite in the Fushun jet is mainly composed of bituminite and sporinite,whereas the liptinite in the Jimsar jet is mainly composed of cutinite.The Raman spectra of the jet samples from these two regions are considerably different from each other because their Raman structural parameters are dependent on the maceral and coal quality.The intensity ratio(I_(D_(1))/I_(G))and area ratio(A_(D_(1))/A_(G))of D_(1) and G peaks of the six jet samples increased substantially with increasing liptinite content and decreased significantly with increased huminite and inertinite contents.The I_(D_(1))/I_(G) and A_(D_(1))/A_(G) values of the Jimsar jet are considerably lower than those of the Fushun jet.It is because the Fushun jet contains a large number of bituminite and sporinite,and the aromatic ring growth exhibited by its molecular structure is poor.Additionally,the I_(D_(1))/I_(G) and A_(D_(1))/A_(G) values of the jet samples from the two regions showed a differential decreasing trend with an increase in the R_(o, max) value.The spatial arrangement of aromatic layers became more orderly with increased coalification degree.These results indicate that Raman spectroscopic parameters can effectively indicate the macromolecular structural difference observed in jet samples of different origins.Furthermore,this will provide a scientific basis for tracing the provenance of jet cultural relics in the future and provide insights into the development history of the handicraft industry and commodity circulation in ancient China.