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细小的铬铁矿自形晶遍存于基拉韦厄熔岩之中。在迅速冷凝的熔岩中,铬铁矿通常被包含在镁质橄榄石斑晶之中,或与其连生。此外它们还呈孤立的颗粒存在于玄武质玻璃之中。这些铬铁矿与橄榄石共生,是基拉韦厄拉斑玄武岩浆的最早的结晶相。铬铁矿及与其共生的橄榄石斑晶的成分系用电子探针进行分析。每次喷发中有一个样品系采自正在上升的熔岩湖的表面,其余样品为浮岩。这类含铬铁矿熔岩的Cr_2O_3含量列于表1,基拉韦厄·伊基和马考普伊铬铁矿的平均成分也列于表1,单个颗粒的分析结果绘于图1之中。
Small chromite self-shaped crystals exist in the Kilauea lava. In rapidly condensed lava, chromite is usually contained in or associated with magnesian olivine plaque. In addition, they are still isolated particles in the basaltic glass. These chromites coexist with olivine and are the earliest crystalline phase of Kilawela tholei basaltic magma. The composition of chromite and its associated olivine plaque was analyzed using an electron probe. One sample from each eruption was taken from the surface of a rising lava lake and the remaining samples were pumice. The Cr_2O_3 contents for this type of chromite-bearing lava are given in Table 1. The average composition of the Kilauea Iki and Magnafi Chromites is also given in Table 1. The results for the individual pellets are plotted in Figure 1 .