绿松石呈色机理实验与论证

Experiment and demonstration of turquoise coloration mechanism

矿物的成分、结构和键型是复杂的,引起矿物颜色变化的因素也是复杂的,一种矿物的颜色往往是多种呈色机制的总效应。绿松石是一种自色玉石,即它的颜色是由自身的成分和结构决定的。颜色正是决定绿松石经济价值的重要因素,长期以来,对绿松石颜色的研究一直是绿松石宝石学研究的重要内容。绿松石的颜色主要由Cu2+,F e3+离子决定,Cu2+离子对绿松石的基色——天蓝色起有益作用,而F e3+则起相反作用,两者含量多少决定了色调的变化特点。这与用晶体场理论和光谱实验观测解释的呈色机制是一致的。

The composition, structure and bond type of mineral is very complicated,and the factors making the color of minerals changed are also very intricate, which mean that the mineral＇s color is usually the general effects of kinds of coloration mechanism. Turquoise is an idiochromatic bowlder, which means its color is settled by its own composition and structure. Color is an important factor for the economic value of turquoise. Hence, the research of the color of turquoise is a significant content for the gemology study on turquoise for long time. The color of turquoise is decided by ions of Cu^2＋ ,Fe^3＋, Cu^2＋is favorable for the basic color of turquoise （sky blue）, while Fe^3＋ is unfavorable for the basic color. The content of both ions settled the changing characteristics of the hue, which is accordant with the coloration mechanism that explained by crystal--field theory and spectrum experiment observation.