Photographer: Sergei Ilnitsky
Experts and local residents of the Republic of Sakha (Yakutia) in Russia say that the bowels of Yakutia contain the entire periodic table. The region’s harsh climate makes it difficult to extract many of the minerals there. But those who mine diamonds are not afraid of the harsh frost in winter and the tropical heat, with clouds of flies, midges, mosquitoes adding to the mix, that can make it tough in summer.
These beautiful, expensive stones are worth every effort, and that is why Yakutia is known as the land of diamonds. The city of Mirny, some 4,155 km east of Moscow, is considered the center of this land. Its history dates back to 13 June 1955, when Soviet geologists Yuri Habardin, Ekaterina Elagina and Vladimir Avdienko discovered what would become known as the Mir kimberlite pipe. Mirny developed near the quarry, and it was where the miners and workers lived. Nowadays it is home to over 35,000 people.
The view from the airplane window upon arrival at Mirny airport reveals a remarkable sight—a huge round hole in the ground—the Mir open cast diamond mine. It has a diameter of 1,200 meters and a depth of more than 525 m. It is one of the largest excavated holes in the world. Operations for open-cast mining started in 1957 and were discontinued in 2001. In 2009, Mir—which had since been operated by Russian diamond producing company Alrosa—was reopened as an underground diamond mine. Experts expect the mine to remain operational for another 50 years.
Alrosa operates 10 kimberlite pipes and several placer deposits in Yakutia. Most are located in remote areas where there are no roads, just swamps, forests and winding rivers. Only in the winter can the ground be driven on for cargo transportation. The company’s main office and Diamond Sorting Center are located in Mirny. All diamonds mined in the region are sent there for testing and sorting for size, weight and purity.
Alrosa’s Nyurbinsky open-cast mine, which is located some 300km from Mirny and was put into operation in 2001, is considered to have a high diamond content. With a depth of 330m that is expected to reach 570m, it is a huge pit extending deep into the ground in the middle of the taiga, which trucks slowly crawl up loaded with kimberlitic ore, an ultra-basic rock made of olivine, phlogopite, pyrope and other minerals. At the quarry, two excavators work to serve up to 20 trucks. Some trucks transport ore while others carry soil that opens the kimberlite base. In one ton of ore, there are 1,000 carats of diamonds on average.
The Botuobinsky pit is located 3 km from the Nyurbinsky kimberlite pipe. In 2015, the Botuobinskaya pipe started ore mining; it contains many gem and near-gem quality diamonds with a high transparency and low proportion of colored stones. Diamond production at the pipe is expected to exceed two million carats when it reaches its design capacity of 400,000 tons of ore per year.
All kimberlite ore is processed at processing plant 16 of the Nyurbinsk Mining and Processing Plant on the Nakynskoye kimberlite field. Rough diamonds are found in hard kimberlite ore, from which they need to be extracted without being damaged. Huge pieces of ore are crushed into sizes of no more than 0.5m. The diamond-bearing ore is then fed into drum mills whereby lumps of ore are reduced in size to 5cm. The slurry of finely ground ore is sent into classifiers that separates the material by density. During the second stage, diamonds are extracted either by X-ray separation, foam separation or heavy separation. Diamonds are then cleaned, sieved, handpicked, sorted and packed into containers and sent by plane to the Diamond Sorting Center in Mirny.
The most important and creative stage of the entire process, however, is the cutting and polishing of the rough stone. The process involves 150 operations and it can take years to cut some stones. These operations normally take place at Alrosa’s polishing facility in Moscow. The diamonds are first sent to the lab to marking specialists, where they are scanned and videotaped to create 3D models of them. Next, technologists and specialists determine the optimal cut shape for the diamond in question. At the same time, the diamond’s estimated price is established. Alrosa develops many of the scanners, electronic devices and computers used by their specialists. If a rough diamond is to be divided into several pieces, it is cut with a laser or saw. For the cutting stage, master cutters use a horizontally-rotating circle of steel covered in diamond powder and oil, which allows the diamond to take on its final shape. In the polishing workshop, the stones are polished with an abrasive wheel. Polishing diamonds is a big responsibility as stones can be easily damaged. Cutters say that over the years they learn how to feel the stones and understand when they should stop and have a break during the process. In 2017,
Alrosa mined a bright yellow diamond at the Ebelyakh placer deposit in Yakutia. It was cut from a crystal weighing 34.17 carats. The cutting process took six months and a team of four specialists worked on it. The diamond weighing 20.69 carats was made into an 'Asscher' shape, a rare choice for a colored diamond. Alrosa’s production totaled about 21 percent of the world’s output in 2018, with a diamond output of about 7.7 million carats.