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对人工合成端员组分无铁蓝闪石Na_2Mg_3Al_2Si_8O_(22)(OH)_2的实验工作进展情况的回顾,可以得出这样的结论,即这个成分的角闪石至今未必合成得了。尽管某些闪石在这些合成研究中,在P_H2O20～30kb的压力下可以得到接近合理的端员组分蓝闪石,但精确的成分以及这些合成产物的地质学上有关的稳定界限还只能粗略的确定。再者,因为蓝闪石Ⅰ和蓝闪石Ⅱ在成分上根本不同,人们不能支持同质多象的概念。所以从这些实验的研究中不可能说明天然蓝闪石稳定性的有意义的资料。在这方面的新进展是来自于法国Ile de Groix的相对贫铁蓝闪石的稳定数据。该数据可以预测这种闪石的最大的P_H2O—T稳定范围。这个特殊的蓝闪石P_H_2O最低在4kb,T>550℃时,可能不稳定。在350℃和550℃之间,最小压力需从4kb升到近10kb。这些最大的可能稳定界限与推断的变质岩区的蓝闪石为高压低温条件基本是一致的。
A review of the progress in the experimental work of synthesizing a terminal non-ferriodite Na_2Mg_3Al_2Si_8O_ (22) (OH) _2 can be concluded that the amphibole of this component has not yet been synthesized. Although some amphiboles have been able to obtain nearly reasonable amphibole in these syntheses at pressures of 20-30 kb P_H2O, the precise composition and the geologically relevant stability limits of these syntheses are only Roughly determined. Furthermore, since melatonite I and amphibole II are fundamentally different in composition, one can not support the concept of homogenous multiple images. Therefore, it is impossible to explain the significance of the stability of natural glaucophane from these experimental studies. New progress in this area is the steady-state data from the relatively poorly glaucophane in Ile de Groix, France. This data can predict the largest P_H2O-T stable range for this amphibole. This particular glaucophane P_H_2O minimum 4kb, T> 550 ℃, may not be stable. Between 350 ° C and 550 ° C, the minimum pressure needs to rise from 4kb to nearly 10kb. These maximum possible stable boundaries are basically consistent with the glaucophane inferred metamorphic rocks for high pressure and low temperature conditions.