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coal mine; (coal) pit; colliery
coal-mine shaft
この地域にはかつて炭礦があった。
There used to be a coal mine in this area.
炭礦が閉鎖されて町は衰退した。
The town declined after the coal mine was shut down.
炭礦で働いていた祖父の話を聞いた。
I heard stories from my grandfather who worked in the coal mine.