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本文讨论华北麻粒岩相带中部（晋冀内蒙三省区边界）地区各种麻粒岩相岩石的石榴石及其与单斜辉石的平衡共生关系。该地区有上部孔兹岩系和下部麻粒岩系两大类岩石组合，麻粒岩中有浅色麻粒岩和暗色麻粒岩。并有部分高压麻粒岩出露。主要造岩矿物都显示麻粒岩相特征。各类岩石中所有的石榴石都无明显的成分分带，只在大颗粒边部约５０μｍ宽的边缘成分稍有变化，Ｆｅ和Ｍｎ增高，Ｍｇ降低，Ｃａ则基本不变。但不同岩石中石榴石成分差别很大。暗色麻粒岩的石榴石高钙富铁，高压麻粒岩的高钙富镁，孔兹岩的贫钙，较富铁。单斜辉石都是次透辉石，其铝含量相对冀东来说比较高，高压麻粒岩的Ａｌ２Ｏ３可高达７％以上，高压麻粒岩中辉石的硬玉分子比基性麻粒岩稍高，石榴石与单斜辉石在各种麻粒岩中都达到了平衡。其平衡的表现之一是在Ｃａ－Ｍｇ－ΣＦｅ图上石榴石、单斜辉石与全岩三者的成分投影点几乎在一条直线上，即全岩成分点落在石榴石和单斜辉石的连线上。这说明石榴石和单斜辉石成分之间有一种内在的规律性联系。这是否可以作为一个普遍规律，如果是，它们之间有无可公式化的函数关系，正在进一步总结和研究。本文只用实例说明了这一事实。
This paper discusses the garnet of various granulite-facies rocks in the central granulite facies belt in North China (the boundary between the three provinces in Jin-Ji-Inner-Mongolian region) and their equilibrium symbiosis with clinopyroxene. There are two major types of rock assemblages in the Upper Khond and Lower Granulites, and the granulites include light-colored granulite and dark-colored granulite. And some high-pressure granulite exposed. The main rock-forming minerals show granulite facies characteristics. All garnets in all kinds of rocks have no obvious zoning. Only the edge components of about 50μm in the edge of large particles change slightly, Fe and Mn increase, Mg decreases, while Ca does not change basically. However, the composition of garnets varies greatly from rock to rock. Dark granulite garnet high calcium iron, high pressure granulite of high calcium and magnesium, khondal rock calcium, more iron. Clinopyroxenes are diopside, the aluminum content relative Jidong is relatively high, high-pressure granulite Al2O3 can be as high as 7%, high-pressure granulite pyroxene jadeite than the basic granulite Slightly higher, garnet and clinopyroxene in a variety of granulite have reached a balance. One of its performance is balanced in the Ca-Mg-ΣFe diagram garnet, clinopyroxene and the whole rock three component projection point in almost a straight line, that is, the whole rock component points in garnet and clinopyroxene On the connection. This shows an inherent regular relationship between garnet and clinopyroxene composition. Whether this can be regarded as a universal law and if so, whether there is an unformable functional relationship between them is being further summarized and studied. This article illustrates this fact only.