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The Mir mine also called the Mirny mine, is a former open pit diamond mine, now inactive, located in Mirny, Eastern Siberia, Russia. The mine is 525 meters deep and has a diameter of 1,200 m, and is the second largest excavated hole in the world, after Bingham Canyon Mine. The airspace above the mine is closed for helicopters because of alleged incidents in which they fell in due to air temperature differences and unexpected currents.
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