Experimental calibration of a mineral reaction is expected to tightly constrain its equilibrium condition as a function of the intensive variables of interest in a specific study. The most unambiguous way of achieving this objective is to determine “reversal brackets” using crystalline starting mixtures of both the reactant and product phases. For an end member reaction, a reversal bracket consists of a pair of closely spaced P-T points at which the product grew at the expense of the reactant and vice versa. The relative proportion of the product and reactant phases are commonly determined by comparing the powder X-ray diffraction...

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3. 实验校准和相平衡研究的一些回忆

矿物反应的实验校准预计会严格限制其平衡条件，作为特定研究中感兴趣的密集变量的函数。实现这一目标的最明确的方法是使用反应物和产物相的结晶起始混合物来确定“反括号”。对于端元反应，反转括号由一对紧密间隔的 PT 点组成，在这些点上，产物以反应物为代价生长，反之亦然。产物相和反应物相的相对比例通常通过比较粉末 X 射线衍射来确定...