一种香石(玉)的矿物种属及香味成分与成因分析

ANALYSIS OF COMPOSITION AND GENESIS OF A KIND OF FRAGRANT STONE(JADE)

针对产自我国某地的一种具有天然奶油巧克力香味的香石（玉），利用常规化学分析、红外光谱分析及X射线衍射分析方法，确定了此种香石（玉）的矿物归属，并用固相微萃取-气相色谱-质谱联用分析技术分析香石（玉）的挥发性气体成份，结果表明：香石（玉）的化学成份w（B）／％为Si0249．02；MgO43．51；Al2O30．48；CaO2．01；Fe2O31．41；H2O^＋11．00。红外光谱具有蛇纹石红外光谱特征，X射线粉末数据亦与蛇纹石吻合，其矿物种属确定为蛇纹石。香石（玉）的挥发成份中有67种有机组分，经鉴定含有18种具有香味的有机化合物，香味成分约占挥发性成分总量的55％左右。蛇纹石是一种层状硅酸盐矿物，呈卷曲的园柱管状结构，这种特殊结构决定了它具有吸附能力，在地质构造运动产生的特殊温度、压力环境下，被吸附的有机物熟化使蛇纹石产生如奶油巧克力的特殊香味。

In the paper,a kind of fragrant stone （Jade） from some place in China with natural cream-chocolate fragrance has been reported for the first time. The mineral spices of fragrant stone （Jade） has been studied by chemical analysis, infrared spectrum analysis and X-ray diffraction analysis and the volatile components of the fragrant stone （Jade） have been analyzed by ana- lytic technique of solid phrase micro-extraction, gas chromatography and mass spectrometry. The results showed that, the chemical compositions of fragrant stone （Jade） are SiO2 49.02% ,MgO 43.51%,Al2O3 0.48%, CaO 2.01%, Fe2O3 1.41%, H2O＋ 11.00%. Its infrared spectrum revealed characteristics of serpentine＇s, and its X-ray powder analysis was identical to serpentine too. Therefore, the fragrant stone （Jade） should belong to serpentine. The volatile matters of fragrant stone （Jade） comprise 67 kinds of organic compositions, of which 18 kinds of organic compounds contain fragrant smell, and the fragrant smell compositions, accounting for about 55% of the whole volatility composition. Finally, the origin and genesis of fragrant smell are analyzed and discussed.