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Oya mine, Motoyoshi, Kesennuma City, Miyagi Prefecture, Japani
Regional Level Types
Oya mineMine
MotoyoshiDistrict
Kesennuma CityCity
Miyagi PrefecturePrefecture
JapanCountry

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Latitude & Longitude (WGS84):
38° 52' 0'' North , 141° 31' 20'' East
Latitude & Longitude (decimal):
38.86667,141.52222
GRN:
N26E80
Type:
Mine
Köppen climate type:
Cfa : Humid subtropical climate
Nearest Settlements:
PlacePopulationDistance
Ōfunato35,418 (2017)28.3km
Ichinoseki62,970 (2017)34.1km
Mizusawa61,281 (2017)44.8km
Wakuya18,334 (2017)49.1km
Tōno26,781 (2017)50.0km
Mindat Locality ID:
19823
Long-form identifier:
mindat:1:2:19823:8
GUID (UUID V4):
0
Name(s) in local language(s):
大谷（おおや）鉱山, 宮城県 気仙沼市 本吉町


A gold and silver mine, started in 1915 and closed in 1971 (1958 production: 362 Kg Au, at average grade 7.4g/t; 107 Kg Ag, 2g/t).
Gold mine, started before at least 1928.

Histrical summary:
Before 1928: already run by hand digging.
1934: floating beneficiation plant was started.
1943: temporaly halt due to aggravation of WWII (see notice).
1950: restarted.
1962: owner changed from Nihon-kogyo (now, JX Nippon Mining & Metal) to Oya Mine Co., Ltd.
1972: mining activity was closed, only beneficiation plant continued.
1976: All facilities were closed.

Notice:
In war situation, gold is one of strategic material (for importing resources).
So, when WWII started, the government at that time encouraged the development of a gold mine.
But in 1943, the gold mines of were suspended by the regulations because it was difficult to secure the resources by import.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Commodity List

This is a list of exploitable or exploited mineral commodities recorded at this locality.


Mineral List


10 valid minerals.

Rock Types Recorded


Select Rock List Type

Alphabetical List Tree Diagram

Detailed Mineral List:

ⓘ Acanthite
Formula: Ag2S
ⓘ Arsenopyrite
Formula: FeAsS
ⓘ Chalcopyrite
Formula: CuFeS2
ⓘ Galena
Formula: PbS
ⓘ Native Gold
Formula: Au
ⓘ Pyrite
Formula: FeS2
ⓘ Pyrrhotite
Formula: Fe1-xS
ⓘ Quartz
Formula: SiO2
ⓘ Sphalerite
Formula: ZnS
ⓘ Tellurobismuthite
Formula: Bi2Te3

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
ⓘNative Gold1.AA.05Au
Group 2 - Sulphides and Sulfosalts
ⓘAcanthite2.BA.35Ag2S
ⓘSphalerite2.CB.05aZnS
ⓘChalcopyrite2.CB.10aCuFeS2
ⓘPyrrhotite2.CC.10Fe1-xS
ⓘGalena2.CD.10PbS
ⓘTellurobismuthite2.DC.05Bi2Te3
ⓘPyrite2.EB.05aFeS2
ⓘArsenopyrite2.EB.20FeAsS
Group 4 - Oxides and Hydroxides
ⓘQuartz4.DA.05SiO2

Other Regions, Features and Areas containing this locality

AsiaContinent
Eurasian Plate
Japan
Okhotsk PlateTectonic Plate

This page contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only. You should never attempt to visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders for access and that you are aware of all safety precautions necessary.

References

Kamitani, M., Okumura, K., Teraoka, Y., Miyano, S., Watanabe, Y. (2007) Mineral Resources Map of East Asia, Geological Survey of Japan.
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