本文選題：成分特征 + 譜學(xué)特征　； 參考：《成都理工大學(xué)》2017年碩士論文

【摘要】：碧璽的礦物學(xué)名稱為電氣石,是晶體結(jié)構(gòu)和化學(xué)成分十分復(fù)雜的含硼硅酸鹽,類質(zhì)同像替代廣泛,形成環(huán)境的變化以及所含微量元素的不同,使得碧璽顏色十分豐富,幾乎所有的顏色以及顏色組合都能看到。電氣石并不是只有單一的的種類,而是一個礦物族,電氣石的主要礦物種類已確定的有18種,如鐵電氣石、鎂電氣石等,大部分寶石級電氣石(碧璽)是鋰電氣石。本論文采用寶石學(xué)常規(guī)測試、寶石顯微鏡、偏光顯微鏡、電子探針、紅外光譜儀、激光拉曼光譜儀、冷熱臺等對不同顏色碧璽的化學(xué)成分、譜學(xué)特征和包裹體進行研究,并探討其生長條件和演化過程。通過寶石學(xué)常規(guī)測試,所選樣品與碧璽的光學(xué)和力學(xué)性質(zhì)基本符合,黑色碧璽相對密度較其它樣品高。部分樣品的相對密度偏低,并且在紫外熒光燈下出現(xiàn)了不同強度的藍白色和白色熒光,與碧璽經(jīng)過充填處理有關(guān)�？梢酝ㄟ^寶石顯微鏡觀察樣品表面特征和內(nèi)部特征,鑒別碧璽是否經(jīng)過充填處理。通過電子探針測試分析,除一塊棕色碧璽樣品屬于鎂電氣石外,其余均屬于鋰電氣石,棕色—黑色系列碧璽顏色較深,透明度不好,常不用來作為寶石,所以說寶石級電氣石—碧璽主要為鋰電氣石。選取不同顏色的碧璽進行紅外光譜測試,測試結(jié)果符合鋰電氣石的紅外光譜特征,紅外光譜還顯示碧璽表面存在著對大氣中水蒸氣、甲烷和二氧化碳的吸收。對不同碧璽樣品的主體礦物、流體包裹體和固體包裹體進行激光拉曼測試,Fe含量的增加,會導(dǎo)致Si-O伸縮振動的拉曼峰和3590cm-1附近[OH]-拉曼峰發(fā)生分裂,也會抑制3650cm-1附近的拉曼峰;氣液包裹體中特征拉曼峰的存在指示包裹體中存在CO_2、CH_4等氣體在偏光顯微鏡下觀察碧璽內(nèi)部包裹體特征。除針狀和管狀包裹體外,其他包裹體較小,數(shù)量少,形態(tài)不規(guī)則,隨機分布。管狀包裹體內(nèi)常被次生礦物和氣液充填。測定流體包裹體的均一溫度、冰點及籠合物熔化的溫度,通過對測試數(shù)據(jù)的分析和計算可知成礦流體的物理化學(xué)條件:溫度范圍為198~392℃,鹽度范圍為2.41~5.41wt%,壓力范圍為518.6×105Pa~722.4×105Pa,低鹽度與碧璽較低的結(jié)晶溫度相一致。
[Abstract]:The mineralogical name of the tourmaline is tourmaline, which is a boron-bearing silicate with very complex crystal structure and chemical composition. Almost all colors and combinations of colors can be seen. Tourmaline is not a single species, but a mineral family. There are 18 kinds of tourmaline minerals, such as ferrotourmaline, magnesium tourmaline, etc. Most gemstone tourmaline (tourmaline) is lithium tourmaline. In this paper, the chemical composition, spectral characteristics and inclusions of different color tourmalines were studied by conventional gemstone test, gemstone microscope, polarizing microscope, electron probe, infrared spectrometer, laser Raman spectrometer, cold and hot stage, etc. The growth conditions and evolution process were also discussed. The results show that the optical and mechanical properties of the selected samples are in good agreement with those of the other samples, and the relative density of the black tourmaline is higher than that of the other samples. The relative density of some samples was low, and different intensity of blue and white fluorescence appeared in UV fluorescent lamp, which was related to the filling of the tourmaline. The surface and internal characteristics of the sample can be observed by gem microscope to identify whether the tourmaline has been filled. Through the electron probe test analysis, except one brown tourmaline sample belongs to the magnesium tourmaline, the rest belongs to the lithium tourmaline, the brown-black series tourmaline is dark color, the transparency is not good, often does not need to be used as the gem, Therefore, gemstone-tourmaline-tourmaline is mainly lithium tourmaline. The infrared spectra of different colors of tourmaline were tested, and the results were in accordance with the infrared spectra of lithium tourmaline. The infrared spectra also showed the absorption of water vapor, methane and carbon dioxide on the surface of tourmaline. The increase of Fe content in the main minerals, fluid inclusions and solid inclusions of different tourmaline samples will result in splitting of Raman peak of Si-O stretching vibration and [OH] -Raman peak near 3590cm-1, and will inhibit Raman peak near 3650cm-1. The existence of characteristic Raman peaks in gas-liquid inclusions indicates that there are gas inclusions such as COD _ 2 and Ch _ 4 in the inclusions. The characteristics of inclusions inside the tourmaline are observed under a polarizing microscope. Except for needle-shaped and tubular inclusions in vitro, other inclusions are small, small in number, irregular in shape and randomly distributed. Tubular wrapping is often filled with secondary minerals and gas-liquid. The homogenization temperature, freezing point and melting temperature of the fluid inclusions are measured. The physical and chemical conditions of the ore-forming fluid are obtained by analyzing and calculating the test data: the temperature range is 198 ~ 392 鈩，

本文編號：1834628