Mirny Mine is an open pit diamond mine located in Mirny, Eastern Siberia, Russia. The mine is 525 meters deep (4th in the world) and has a diameter of 1,200 m and is the second largest excavated hole in the world, after Bingham Canyon Mine.
The mine is so big and giat that the airspace above the mine is closed for helicopters because of a few incidents in which they were sucked in by the downward air flow.
The mine was discovered on June 13, 1955 by Soviet geologists Yuri Khabardin, Ekaterina Elagina and Viktor Avdeenko during the large Amakinsky Expedition in Yakut ASSR. They found traces of volcanic rock kimberlite which are usually associated with diamonds.For this discovery, in 1957 Khabardin was given the Lenin Prize, which was one of the highest awards in the Soviet Union.
To give an idea how big it is here is is a fine illustration.
The development of the mine had started in 1957 in extremely harsh climate conditions. Seven months of winter per year froze the ground, which was hard in winter, but turned into sludge in summer. The entire mine had to be covered at night to prevent the machinery from freezing.
In the 1960s the mine was producing 10,000,000 carats (2,000 kg) of diamond per year, but the production rate slowed to 2,000,000 carats (400 kg) per year near the pit bottom. The largest diamond of the mine was found on 23 December 1980; it weighed 342.5 carats (68 g). The mine operation was interrupted in 1990s at a depth of 340 m after the pit bottom became flooded but resumed later.
The Mir mine was the first and the largest diamond mine in the Soviet Union. Its surface operation lasted 44 years, finally closing in June 2001. After the collapse of the USSR, in the 1990s, the mine was operated by the Sakha diamond company, which reported annual profits in excess of $600 million from diamond sales.
Currently, the mine is operated by Alrosa, the largest diamond producing company in Russia, and employs 3600 workers. It has long been anticipated that the recovery of diamonds by conventional surface methods will saturate. Therefore, in 1970s construction has started of a network of underground tunnels for diamond recovery. Production of diamonds by this method started in 1999 and is estimated to last for another 27 years. This estimate is based on depth explorations down to 1220 meters. In order to stabilize the abandoned main pit, its bottom was covered by a rubble layer 45 meters thick.
No comments:
Post a Comment