1. Six samples with different colors, textures, etc., were selected according to the depth in the soil derived from granodiorite at Ogoe, Fukushima Prefccture.
2. After the collected materials in wet state were treated with 6% H₂O₂ in order to disolve organic matters, they were dispersed in the NaOH solution with. pH 8.5. These dispersed materials were separated is eight fractions by sedimentation method and centrifugation, and then the iron-hydroxide were removed by using Truog's method.
3. The mineral compositions of the sand fractions with diameter over 0.02mm were quantitatively investigated under microscope. The materials of the fractions of <0.2μ and 0.5-1.0μ were studied by means of X-ray powder photograph, chemical analysis and differential thermal analysis.
4. From these experiments it was confermed that nontronitic montmorillonite, halloysite, kaolinite, degraded illite and their interstratified mineral occur in the soil profile
5. It seems that the nontronitic montmorillonite was formed at the early stage of the weathering of granodiorite rich in bases.
6. It has been followed by the formaticn of halloysite and kaolinite.
7. The change of soil condition seems to be the cause of the formation of interstratified mineral.
8. In finer fraction halloysite is contained far more than kaolinite, while kaolinite is much more in coarser fraction.
9. The degraded illite is a weathering product cf biotite.

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The chromite bodies at the Hiroosa mine consist of massive chromite, of grains disseminated in serpentinite.
In thin section the dusty magnetite and yellowish brown chlorite are abundant in darker variety of serpentinite, but in greenish serpentinite those are scarcity.
Chromite in serpentinite rarely has black margins and is crossed by black opaque material, presumably ferrian chromite or chromian magnetite.
Chromite samples analyzed by the present writer gave a content of CT₂O₃ ranging from 47 to 52% and Cr/Fe ratio of 1.7 to 2.1. It appears likely that there may be systematic variation from spinel molecule to magnetite molecule in composition of the chromite. It seems that FO₂O₃ is concentrated in the residual solutions.

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In this paper, the experimental data on behaviour of bornite in melted sulphur are described. When bornite is sealed in pyrex tubes with sulphur powder and then heated in an electric furnace, the following process is observed.
1) At temperatures higher than 120°C, bornite reacts to form covellite with melted sulphur (Figs. 1A, 6). When cracks are found in bornite, the covellite is produced also in veinlets or as network along them, similar to those of supergen origin (Fig. 1B).
2) At temperatures from 140°C to about 450°C, chalcopyrite appears in bornite in the forms of lattice, emulsion, lens, semi-cell, droplike and worm-like crystals. The lattice pattern is formed at temperatures from 140°C to 320°C in bornite only near covellite, while the drop-like crystals appear in the inner part of bornite at temperatures higher than the former. The lenticular granules often appear in pairs when heated for one hour at temperatures from 250°C to 350°C (Figs. 4, 6), and they change into drop-like crystals when heated at higher temperatures or for longer times. These various forms of chalcopyrite are thought to be an unmixing product from a solid solution, formed in association with covellite.
3) At temperatures higher than 300°C, a reddish brown mineral is formed in bands or patches in bornite, adjacent to covellite (Figs. 6B, 9B). This mineral resembles bornite, but is anisotropic very strongly.
4) At higher temperatures than 360°C, fine granular pyrite newly appears in bornite and also in massive chalcopyrite, originally existed.
From these results, the wirier infers that:
a) It is probable that some ore minerals are formed by thermal dissociation in solid state, as mentioned above.
b) The unmixing phenomena from a solid solution, formed by mechanism of a), can be expected in geological process.

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The Kaaenosawa mine is located about 5km northwest of Horobetsu station, Iburi province, Hokkido.
The hollocrystalline rock, intruded into the Neogene formations,
is found in the neighbourhood of this mine. Especially, the relationship between this plutonic rock and metallic ore deposit, which has been discussed, is clear at this mine.
The geological complex, developed in the adjacent area of this mine, belong to the Neogene Tertiary, various kindes of volcanic, and Quarternary sediments. The Neogene Tertiary consists of the lower green tuff, quartz-diorite intrusived into the former rock (Fg. 3 showing its intruded relation), conglomerate and, upper green tuff in ascending order. The conglomerate is composed chiefy of chert and slate derived from the so-called Palaeozoic, and subordinately of diorite and green tuff derived from the Tertiary member. Its traced distance is very short, the thickness being about 60cm. Covering the Tertiary formations descrived above, the Quarternary sediments and volcanic, are widely developed through the elevated plateau of this district. They are mainly composed of the Noboribetsu mud lava and pumice bed in ascending order.
The ore deposits are embraced in the lowei green tuff, diorite and upper green tuff. Especially, the deposits which are now under mining are a vein-like type in the fault zone striking in N 80°E and in the brecciated none of diorite striking N 10°E. On the other hand, the network type deposits, which had produced. the higher trade ore of Au, Ag in the earlier development of these mine, are embraced in the clayed zone of Lower green tuff. Furthermore, the deposits showing the same mineral assemblage as in diorite, also exsist in the upper green tuff, covering the dicrite and the lower green tuff.
It is clear, accordingly, that the mineralization began after the deposition of the upper green tuff, and then the ore depcsiton here was. ultimately unrelated to the intrusion of quartz diorite. As covered by the Quarternary rocks, the accurate age of mineralization is unclear, but it is doubtlessly younger than the later Kunnui stage.

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