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近年来,堇青石中水的存在问题已引起许多作者的注意。虽然很早就对这个问题发生了兴趣,但仅限于矿物学方面。主要的疑难是,堇青石的化学式究竟应以(Mg,Fe)_2Al~4Si_5O_(18)来表示还是以(Mg,Fe)_2Al_4Si_5O_(18)nH_2O来表示。这里需要强调的是,天然堇青石总是含有一定量的水,虽然曾多次在无水参与的情况下,人工合成了堇青石(Rankin & Merwin 1918,Schreyer & Schairer 1961)。这是堇青石和绿泥石,黑云母和角闪石之间的重要区别,后者原则上不能在干状态下合成。
In recent years, the problem of water in cordierite has attracted the attention of many authors. Although this issue has long been interested, it is limited to mineralogy. The main difficulty is whether the chemical formula of cordierite should be expressed as (Mg, Fe) _2Al ~ 4Si_5O_ (18) or (Mg, Fe) _2Al_4Si_5O_ (18) nH_2O. What needs to be stressed here is that natural cordierite always contains a certain amount of water, although cordierite has been artificially synthesized on several occasions without water (Rankin & Merwin 1918, Schreyer & Schairer 1961). This is an important difference between cordierite and chlorite, biotite and amphibole, which in principle can not be synthesized in the dry state.