The sulphur deposits at the Zao mine are made up of a group of platy formed replacement bodies of sulphur and iron-sulphide ores, and are found in andesitic rocks of the Zao volcano.
Various kinds of altered rocks, such as sulphurized, pyritized, opalized, alunitized, kaolinized rocks and altered andesite, show zonal distribution around the high-grade ore bodies and the fractured zones. Chemically, the formation of these altered rocks is characterized by a leaching process. A large proportion of Ca, Mg, Fe and a small proportion of Al and silica have been removed from the original rocks without change in the apparent volume of the rocks. Only two components, S and H₂O, are found added in larger proportion from mineralizing fluid to the altered rocks.

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The ore deposits of the Kasuga mine and Akeshi, mine, located about 6km west and 10km east of Makurazaki city, Kagoshima Prefecture, are those of epithermal origin.
The gold deposits of net-work type are found in silicified rocks formed by hydrothermal alteration from the andesitic tuff, tuff breccia and propylite of Tertiary age.
Vertical and horizontal zoning of minerals in alteration zone of silicified rocks are as follows:
i) Vertical zoning from upper part to lower in the central area; silicified zone→alunite zone.
ii) Horizontal zoning from inner part to outer;
Silicified zone→dickite zone→limonite-kaolinite zone→kaolinite zone→original rock.
The metallic minerals of the ores include native gold, luzonite, enargite and pyrite. Among them enargite is the most characteristic in the Kasuga mine, and luzonite in the Akeshi mine.
From the observation of about 1, 000 gold particles on polished sections of gold ore from Akeshi mine, it is concluded that native gold is intimately associated with luzonite and pyrite, and apparent mean size of gold particles is 15μ

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The "Kajikas", namely, bonanzas in rhyolite of the Ashio Mine, may be divided into the following three types according to the relations of geological structure.
1. Bonanzas have been formed due to replacement of chert blocks, and large xenoliths in rhyolite.
These bonanzas were deposited by the same factors as the Arikoshi bonanzas and the Renkeiji, i.e., chert was replaced by mineralizing solution which ascended along the folding axes and the intersections of shear veins.
2. Bonanzas in the shattered and brecciated portions:
a. Ore shoots are localized by vein intersections ; —Vein intersection is one of the general factors in forming bonanzas. The Honguchi Kajika was formed along the intersections of shear veins and more than two tension fractures connecting with each other.
b. Bonanzas have been formed at shattered and brecciated zones developed frequently near tension fractures.
c. Bonanzas situated in brecciated rock bodies ; —G. ASANO supposed that the pseudoconglomerate, named by him, may have been formed by the local kettle-depression in the very center of rhyolite, but, it is possible that these rock bodies were formed by shattering and brecciation near the intersections of master shears, 2nd order ones, and tension fractures, and then the interspaces of breccias were intruded and filled with rhyolitic pebble dyke.
The bonanzas are formed in such shattered bodies.
d. Bonanzas are formed near the intersections of master shears and shears of second order ; —The veins in Ashio are divided into two groups of shear veins, and one of their directions is N 45°E, and the other N 75°W, and shears of 2nd order were commonly developed from them.
3. Ashio rhyolite mass consists possibly of alternations of flow, tuff breccia and tuff, and most part of the tuff is of welded-tuff type one. Veins deviate or branch into numerous narrow veins in tuff or tuff breccia, and bonanzas ore bodies are widely found in them.

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Ta-Li-Tzu Iron Mine lies south-west of Lin-Chiang, along the upper stream of the River Ya-Lu-Chiang. This district is composed mainly of Proterozoic sediments or schistose metamorphic rocks, though biotite-granite has intruded into the Proterozoic rocks at the head portion of the, Valley Ta-Li-Tzu.
Ta-Li-Tzu Iron Mine is the most important iron mine in Eastern Manchuria, and the iron ore deposits in this mine can be divided into three types. One of them is a, hematite ore bed or vein?, intercalated with the Lower Proterozoic phyllite formation, probably of the Kai-Ping Series, and forms a most profitable iron ore deposit with a high grade ore. The next one is the Upper Proterozoic mang-aniferous iron ore bed described in detail in this paper. The third one is the skarn-like iron silicate mass in the thermally metamorphosed Upper Proterozoic quartzite, and it has been demonstrated to be a thermal metamorphic derivative of the ore of the second type.
The manganiferous iron ore, which has been called by some to be a chamosite iron ore as well as a pisolitic iron ore, forms a bed of two meters or more in thickness, but sometimes it thins out to a mere trace. This ore has a marked pisolitic structure. The pisolites are 0.5-2.0 cm in diameter, con-sisting mainly of the alternation of iron-chlorite-hematite onior-skin layers with more or less fine, scattered siderite, manganosiderite and fine quartz sand. It is also conspicuous that the nuclei of the pisolites are usually composed of fragments of matrix, in which exist a considerable amount of angular or subangular fine quartz sands. The minerals constituting the matrix are mainly manganosiderite and quartz sand, with variable amounts of iron-chlorite and hematite.
The thermal effect of the biotite-granite, probably of Cretaceous intrusive, given to the ore begins with the diminishing or disappearing of fine siderite scattered originally in the pisolite iron-chlorite, forming magnetite grains by its decomposition. Other component minerals such as manganosiderite and iron-chlorite have merely been recrystallized.and increased in their grain size.
The effect of high grade thermal metamorphism can be observed near the contact of the graniteat the head of the Valley Ta-Li-Tzu. In this case the manganiferous iron ore has changed to skarn-like, massive, dark gray ore, but the question of the origin of this peculiar ore can be resolved by the existence of the relic of pisolitic structure in some examples and also by the resemblance of its chemical composition to the manganiferous iron ore, though some of the chemical components such as carbon dioxide have been totally lost.
In the special example of the skarn-like ore, which retains its original piosolitic structure after its mineralogical reconstitution, the pisolite consists of almanditic garnet, magnetite and hematite. The matrix, on the other hand, is composed of knebelite, dannemorite and a little of tephroite. These mineral composition possibly correspond clearly to the original one, without wider diffusion of elements, though some silica should have been obtained from granitic emanation.

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