The Sazare Mine is located east of the Besshi Mine. It was operated almost continuously from 1930 to 1945 under various cwners and milled 4, 500 t pm of ore containing 1.5% copper.
Later prospecting activities by the Sumitomo Metal Mining Co., Ltd. have been encouraging. In 1953, new ore bodies were discovered by extensive diamond drilling and as the result of development and exploration, it was found that the ore bodies, having an en echelon arrangement, have mutual continuity as mineralized layers. Both sides of the ore bodies can be traced for distances of about 2, 500m. From outcrops to deep levels, the west ore bodies contain more copper, a mine having an output of 350t pm in copper falls into the rank of an important mine in Japan. The bedded cupriferous pyritic deposits of the mine are found in a series of highly schistose green rocks belonging to the Yoshinogawa formation which are believed to be of pre-Carboniferous age (the Sambagawa metamorphic rocks), and lie on the south limb of the main anticline, called the Yakushi anticline. The present form of the ore bodies was controlled by a main and minor fold of different orientations which were formed after the deposition of the original, bedded, mineralized alyers. The direction of pitch of ore bodies is SW and coincides with that of the ores of the minor fold.

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Some characteristic figures for the distribution of trace elements in specimens from altered zones and ore bodies of the Kamikita and Aomori Mines, Aomori Prefecture, are presented.
Gallium, lead, tin, chromium, vanadium, nickel and cobalt were determined spectrographically. Lead, vanadium and tin content increases regularly from the outer to inner zones of the Honko Deposit, Kamikita Minc. Tin is detected only in a pyrophyllite zone of the Honko Deposit. This is also the case in the Aomori Mine, where tin is detected in a zone transitional to the pyrophyllite zone from a kaolinite zone.
A geochemical coherence among trace elements is discussed for each altered zone.

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(1) The average size of the workable, impregnated, metasomatic sulphur deposits in Japan is 256m in diameter (321m×192m) and 29m thick.
(2) The ore deposits are generally found in irregular konides, and never in regular konides.
(3) The dip of the ore deposits depends upon the bedding of the country rock ; consequently, it, is slightly under 15°, which is nearly the same as the slope of the skirt of the konide.
(4) From the nature of volcanic structures, it can be expected that fumaroles, steam vents, ore deposits, volcanic bed-rock and hot-springs will be distributed in zones of decreasing altitude according to the order given here, however the relative altitudes of these zones will not vary greatly from each other.
(5) It follows from (4) that the ore deposits are to be found between the steam-vent and hotspring zones. Because of topography, it is clear that ground water is better developed in the hot spring zone than in the steam vent zone.
(6) It follows from (5) that one is most likely to find ore deposits in the zone of the break in slope between the breast and skirt of the konide.
(7) The dissection of a volcano begins at the top of the konide and ends on its skirt. Therefore, the location of the ore deposit is not liable to be affected easily by dissection because of the time lag involved and also because of the following probabilities.
(8) The interval between adjacent radial valleys of a volcano averages about 1km whereas the diameter of the ore deposits, as mentioned above, are on the order of about 256m, the ratio being roughly one to four. Therefore the probability of an ore deposit being dissected by a radial valley is rather small.
(9) Further, the ore deposits are considered generally to lie at depths of from 150m to 200m, whereas the depth of the radial valleys measures at most only 50m. Therefore the probability of an ore deposit cropping out is expected to be small.
(10) When the size of the sulphur deposits in Japan is considered, it is found that the size of the Matsuo deposit exceeds by far that of other deposits such as Abuta and Zao. Deposits still smaller than those of Abuta and Zao are abundant. These facts indicate the probable existence of hitherto undiscovered ore deposits, the size of which lie between those of Matsuo and Abuta-Zao.
(11) From (7), (8), (9) and (10), we can presume a high probability for future discovery of many more ore deposits in Japan, provided we prospect untiringly.
(12) In view of the aforementioned small probability that the ore deposit will crop out, the use of geophysical and geochemical prospecting methods are recommended.

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The Kamioka Mine, working the largest lead-zinc deposits in Japan, lies in the eastern corner of the Hida gneiss complex. Around the mine, lenticular crystalline limestone beds are often intercalated among biotite-hornblende gneiss which is generally disposed in a NE direction and has NE fold axes which pitch 45°SW.
The ore deposits are closely related to the crystalline limestone beds by pyrometasomatic replacement which attacked some minor folding crests to form typical skarn ores of the so-called "Mokuji ore body". The "Shiroji ore body" is a peculiar type of deposit intimately related to the skarn Mokuji ore body. It carries the distinct features of a hydrothermal deposit and is localized in narrow spaces controlled by fissure intersections which are quite different from those of the Mokuji ore body.
The Shiroji ore body includes sphalerite, galena, chalcopyrite, pyrite, hematite, arsenopyrite, and silver minerals as ore, and quartz, chlorite, sericite, and carbonate as gangue. The ore is enclosed in a zone of silicification consisting of quartz-(adularia)-sericite-carbonate. All surrounding rocks have been strongly altered by silicification, sericitization, chloritization, feldspathization and argillization.
The fracture system controlling the Shiroji ore body is disposed regularly in three directions, namely, NE, NS and EW. The intersections of the fractures trend NE and pitch 45°SW, and offer excellent room for ore deposition.
Based on the field occurrence, the mineral assemblages and the nature of the wall rock alteration, the writer concludes that Shiroji ore bodies were produced under hydrothermal(mesothermal) conditions which followed deposition of the pyrometasomatic Mokuji ore bodies.

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