The Himekami pluton is a complex of mafic rocks and their differentiated felsic rocks, which belong to shoshonite rock association. The pluton is devided into three bodies: South pluton, North pluton and Shiroishi pluton. The South pluton, consisting mainly of monzonite, monzogabbro, quartz monzonite and quartz monzodiorite, is classified genetically into four groups of mafic and felsic rocks. Each rock group accompanies a few amounts of xenolithic mass of cumulated, ultramafic rocks and melagabbro. The North pluton is a zoned pluton of quartz monzonite, granite and granodiorite. The Shiroishi pluton is a leucocratic tonalite-granodiorite.

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Two kinds of magma are probably derived from the initial magma in the Himekami pluton. The content of magnesium is the major difference between the two magmas. They produce the present four rock groups through two different processes in which the ratio of FeO to FeO^* decreased, or did not change largely. Both processes are well explained with the removal of cumulates in some combinations of olivine, pyroxenes, plagioclase, magnetite, biotite and hornblende.
The North pluton was differentiated through the process in which the ratio of FeO to FeO^* decreased. The Shiroishi pluton is the latest-stage product of the differentiation.

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Total sulfur content has been determined in sedimentary rocks by a iodometric titration method. The sulfur content in GSJ and USGS standard samples could be analyzed with good precision. A high halogen content in the samples, however, seriously affects the analysis: e. g., values of the sulfur content decrease significantly, when NaCl is more than 5 mg.

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Cordierite from the granulite facies crustal segment of southern India shows entrapped CO₂ within matrix channels and fluid inclusions. A combination of, visual decrepitation and stepped thermal analysis for CO₂ extraction distinguishes the inclusion and channel fluids, and allows the prediction of CO₂ zonation in cordierites crystallizing in deep crustal environments.

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