The efficiency of a company mining geologist is apt to be evaluated by the profits of his mine or company, although it depends upon the original native of the mining field he worked and also upon its condition of mine operation. It is often true that reports on a specific mine or field prepared at the same time by different geologists give different impressions to mine managers or directors. This is especially true when the visual data on the deposits are few and the resulting interpretations differ widely.
The training of a mining geologist is not ended with only training in standard methods or practices. These provide only the fundamental grounds to the mining geologists. To be fully successful, his work must provide the basis for correct managing ideas to the managers or directors. Thus, training on reporting or description, well integrated with the current economical situation is necessary.

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The bedded cupriferous pyritic deposit of the Iimori mine is concordant in green schist of the socalled Sambagawa zone. The ore deposit is a tabular body, 0.2-2.8m thick and extends 250-300 m along the dip. The linear direction of the ore-body coincides with the lineation observed in the country rocks.
Petrofabric analyses indicate that the prevailing schists of the district are B-tectonites and the direction of the lineation coincides with the B-axis. Thus the linear direction of the ore-body of the bedded cupriferous pyritic deposit of the Iimori mine, coincides with that of the B-axis.
The joints nearly perpendicular to the direction of the lineation predominate in the schist and ore-body.
The quartz-grain fabric of the commonest schists shows the ac-girdle distinctly, further the acgirdle is imprinted on the quartz-grain fabric of the banded ore. The grain fabric of quartz filling the interstices between pyrite crystals in the compact massive ore has no recognizable regularity.
The genesis of the ore deposit remains unknown. However, it is considered unheldly that the ore deposit was formed after the metamorphism and deformation of the country rocks had ceased completely. The ore deposit may be a pre- or para-kinematic deposit.

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The iron oxides and iron sulphides of the Kamaya mine, located about 12 km northeast of Datemonbetsu, Iburi Province, Hokkaido, are of hydrothermal origin. In this area liparitic tuff and tuff breccia sediments of the Miocene Toyoura formation have been intruded by propylite, nevaditic liparite and andesite dikes, and later covered by flows of two-pyroxene andesite lava.
The iron ores are generally irregular, massive deposits within the nevaditic liparite and breccia tuff. These ore bodies consist of reddish brown iron ore and some blackish iron sulphide. Ore and associated minerals are quartz, iron ore (hematite), pyrite, marcasite, and sericite.
The most characteristic feature of the iron ores is their higher iron content and lower combined-water content than so-called "limonite" in the zone of oxidation. The ore is red to reddish black, has a micaceous luster, and gives a reddish brown streak. In thin section this iron ore is opaque and ussually associated with quartz. Its X-ray powder pattern is very similar to that of artificial Fe₂O₃. Chemical analysis gives Fe₂O₃, 88.40% ; H₂O (+), 0.34% ; H₂O (-), 1.72%; and insoluble residue, 8.33%; total. 98.79%.

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It is well known that for the Nogata Stage, one of the main coal-bearing stages of Palaeogene Tertiary in Northern Kyushu, a marine facies corresponding to it is present. However, for the Otuji Stage, the upper coal-bearing stage of Nogata Stage, the presence of a corresponding marine facies has not yet been reported. The writer and his colleague have discovered the missing marine facies by the observation and studies of date from many borings made by a few coal mining companies in Karatsu Coal-field, Saga Prefecture. The Yoshinotani Beds, the main coal-bearing beds of Karatsu Coal-field and correlative to the Otsuji Stage, have been demonstrated to be overlain unconformablly by the Kishima Beds. The Yoshinotani Beds, have also, been demonstrated, with four zones of marine fossil-bearing beds. Three of these lie each above the main coal seams or groups of seams, and the fourth occupies the uppermost horizon of Yoshinotani Beds. In the Ureshino district, the southern margin of Karatsu Coal-fields, the coal seams of the Yoshinotani Beds are entirely absent, only the marine facies of them are present. The change in facies of deposition of Yoshinotani Beds from north to south, i.e. offshore, is summarized as follows : the normal coal-bearing formation with workable coal seams—interfingers of marine beds and terrestrial coal bearing beds—pure marine beds of same stage. The writer and his colleague have proposed the name "Kawago Beds" for this marine facies of the Otsuji Stage of the Karatsu Coal-field. The name is derived from the locality of Kawago in City Takeo.

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