The contact metasomatic and the vein-type ore deposits of the Shin-Kiura tin mine have been worked since old times for tin, silver, arsenic and copper. These are characterized by complex mineralization at a wide range of temperature related to the Tertiary granitic intrusion. Recently, lollingite-cassiterite-quartz-wollastonite vein-like deposits, containing native gold, native bismuth and tellurobismuthite, have been found in the Uriya-Kaneko adit of this mine.
In this paper, mineragraphy of the Au-Te-Bi-As ore is presented, and genesis of the similar mineralizations in Japan is discussed.

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Stibnite, cinnabar and realgar are well known as the epithermal low temperature minerals. It is said that stibnite crystallizes at deeper place, at higher temperature, and in earlier atage than cinnabar, and realgar shallower, lower, and later than cinnabar.
On the basis of the samples from Alaska, Sarawak (British Borneo), and Hokkaido (Japan), the writers have learned the following points:
1. The general tendency of the order of crystallization of the abovementioned minerals is believed tobe, stibnite→cinnabar→realgar.
2. Writers have found, however, a case where cinnabar crystallizes in an earlier stage than stibnite and a case where it crystallizes in the same stage as stibnite and realger. This means that the condition of crystallization of cinnabar has a wider range than that presumed before.
3. As far as judged from iron sulfide minerals, the ore solution is supposed to change its pH during crystallization of these minerals, from alkaline to acidic. But as to the change of pH at the stage of clay mineral formation, further geochemical examinations are required.

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In the Tanba district, which occupies the area of thick sedimentary accumulations in the "Chichibu" Palaeozoic geosynclinal terrain, accompanied by some intercalations of "diabase and schalstein", there have been found many silica deposits mined for important refractory raw materails in Japan. The deposits occur sporadically on the surfaces of the submarine flow sheets of the "diabase", and assume thick lenticular forms. Hematite impregnations are usually recognized in the rocks of the upper next horizons of the sheets. The silica rocks are composed of fine-grained red (or green) cherty rock fragments and coarsegrained white matrix made of segregated vein .quartz. Spherical, subspherical, and/or angular fractures define the outline of the fragments of the cherty rocks. From these critical and some other geological occurrences as well as from the petrographic features of the silica rocks, it is concluded that the deposits were formed by the segregation of the vein quartz in the fractured cherts which were precipitated originally as the colloidal silica (with small amounts of iron oxides) from some postvolcanic emanations from the surface of the submarine"diabase"flows. Judging from the structural relations of the deposits, the geologic age of the quartz veins is older than the Mesozoic granite intrusions in the district.

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Emery deposits have recently been found at the Shin-Kiura mine, Oita Prefecture, the first occurrence in Japan. The emery ore, being composed predominantly of corundum, spinel and iron oxides, is closely associated with Paleozoic limestone. The writers present here the mineralogical and chemical compositions of the ore.
Corundum is often contained as much as 60% in the Kiura emery, which shows tints of blue due to the presence of sapphire. Spinel constituent of the emery belongs to hercynite, which is always existent, in a large quantity. The emery often contains also considerable quantities of magnetite, ilmenite and andalusite. Anorthite and alkali-amphiboles are seen frequently as accessory minerals along with some garnet, tourmaline, cordierite, biotite, titanite, quartz and calcite. It is noteworthy that hematite and sulphide minerals are scanty in the emery ore.
The main chemical constituents of the emery ore are AL₂O₃ (35-65%) and Fe₂O₃+FeO(30-55%), with a subordinate content of SiO₂, which ranges from 5% to 20%. The Kiura emery is characterized by low MgO content and high CaO content, as compared with emery ores of other localities.
The Kiura emery deposits are thought to have been formed mainly by contact metasomatism, as a reaction between basic igneous emanations and the Paleozoic limestone: The origin can be ascribed to a process of desilication of the igneous media by limy or peridotitic rocks.

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