The Mir Kimberlite Pipe is an opencast mine located on the left bank of the mid-channel of the Irelyakh River (the right-side tributary of the river Vilyui) in the immediate vicinity of Mirny, Yakutia. Given its depth of 525 meters and a diameter of 1.2 kilometers, it is one of the world's largest opencast mines.

The kimberlite pipe was discovered on June 13, 1955 by the geologists of the Amakinsky expedition – Y.I. Khabardin, E.N.Yelagina and V.P. Avdeyenko. At the first stage of researching the field, the Mir pipe was explored to a depth of 600 meters. Further exploration was conducted to depth of 1,235 meters and diamond reserve calculations were performed to the same depth.
       
Since 1957, the field was developed using the open-cut method and extraction of diamonds was conducted for 44 years (until June 2001). Near the opencast mine is the settlement of Mirny, which became the hub of the Soviet diamond-mining industry. The largest diamond found in Russia was extracted at the Mir mine on December 23, 1980. It weighs 342.5 carats (more than 68 grams) and was called “The 26th Congress of the Communist Party of the Soviet Union.”

In the course of its operation, the opencast mine was renovated three times. A unique backfill barrier preventing the inflow of aggressive brines from the Metegero-Ichersky aquifer system was developed, as well as a mine drainage system of 32,250 cubic meters of water per day (approximately 1 million cubic meters per month).

In the years of operation using the open-cut (opencast) method, $17 billion worth of diamonds (based on informal data) was extracted from the field, and about 350 million cubic meters of rock refuse were removed.

Geological research showed that the occurrence depth of the diamonds is more than one kilometer; therefore, Alrosa, which is currently developing the field, is building an underground mine on the field. In order to build the underground mine and facilitate the future safe mining of the top subsoil horizons, the bottom of the preserved opencast mine was filled with a special safety layer of rock refuse. This “pillow” or “bearer,” does not give in to explosive pressure; it is 45 meters thick.

The underground mine is currently under construction at the field. In March 2009, at the underground mine Mir, which is also under construction, a unique engineering operation was successfully completed – on March 26, 2009, erection and installation of the head frame of a 52-meter-high cage shaft weighing more than 800 tonnes was finished.

The decision to erect the head frame away from mountain development was made two years ago, with a view to reducing the construction time of the Mir underground mine. The advantage of the applied method is that it allows work on sinking the cage shaft and head frame simultaneously, which in turn facilitates shortening the time until commissioning of the underground mine Mir by at least a year.