淬火天然与合成紫黄晶显微中红外光谱研究

紫黄晶是珍贵的水晶变种，其紫-黄色区域分别具有特征的中红外吸收光谱，在不同温度具有不同变化规律，这些规律无法在单次、单点实验中加以总结。实验通过热处理和显微红外光谱技术，对不同温度淬火紫黄晶的紫-黄色区进行线扫描，分析一系列温度、空间变化下的中红外光谱，实验表明水对于紫黄晶的颜色影响不大，在加热过程中谱线会发生规律性变化。紫色区3 585和3 614 cm-1尖锐峰、3 400 cm-1附近宽泛峰同时变化表明宝石在受热过程以结构水变化为主，而受热后紫色区的特征峰减弱及黄区特征峰增强的现象可能与结构水中H+或其他阳离子的移动有关。同时发现对于热处理产生的黄晶，中红外光谱仍保持紫晶特征吸收光谱。

The Micro Mid-Infrared Spectral Study on Quench of Natural and Synthetic Ametrine

Ametrine is the valuable variety in alpha quartz, and its mid-Infrared (MIR) spectra research helps to understand the differences of violet and yellow zones in amtrine. The natural and synthetic ametrine have the specific MIR absorption spectra in the violet-yellow color zones respectively. When quenched under the different temperatures, the spectra can change regularly. We conducted quench experiments of natural and synthetic ametrine using tube furnace and collected the micro MIR spectra of natural and synthetic ametrine under different quench temperature in the violet-yellow color zones. The experiments suggested that water had not direct correlation to do with the color. In sharps peak at 3 585 and 3 614 cm-1 of violet zone and broad band near 3 400 cm-1 of yellow zone, the simultaneous changes of these peaks, which occurred in same temperature, indicating that when the samples heated, the structural water may play a dominant role in change. During the heat treatment, the peaks decreased in violet zone while increased in yellow zone, that could be explained by the migration of H+ or other positive ions through the structure channels of alpha-quartz. At the same time, the research pointed out that the MIR spectra of heated yellow quartz is largely similar to the amethyst one.