Most solid diamond is the world. Many of the materials other than high hardness, cut by these stones, but he cut diamond can be another diamond.
Appreciate this mineral is not only the hardness, but also for beauty.
The chemical composition of the diamond - "closerelative "of coal and graphite. It consists of the same chemical element - carbon, but differs in the crystal lattice structure. To grille has changed, thereby transforming the graphite into diamond, need temperatures of 1100 to 1300 ° C and a pressure of about 5,000 atmospheres. Such conditions are at 100 to 200 km depth.
deposits of diamonds
When the break through the crust gases,crack rushes volcanic magma, which brings the diamonds from the earth's depths. The magma solidifies, forming a special breed - Kimberlite occurs kimberlite pipe, narrowing from top to bottom. Its diameter can vary from 10 to 20 meters, and the area - from 0.01 to 140 hectares. It looks like the primary, or native diamond deposits.
Kimberley, as well as other species, subject toand weathering degradation by chemical reaction with water, carbon dioxide and other substances. With the expansion and deepening of river valleys of diamonds from kimberlite pipes collapsing captured water flows, and found themselves in the bottom of the river sediments. Thus arose the secondary deposits of diamonds, they are called placers.
Before the 2nd half of the XIX century, diamonds are mined only in alluvial deposits, but now 85% of the diamonds mined in kimberlite pipes.
Diamond deposits are found on all continents except Antarctica. However, even there, they found pieces of a meteorite containing diamonds. Especially a lot of diamond deposits in Siberia and Africa.
The process of diamond production
Diamond mining - the process complicated and expensive. It begins with the search field, it takes decades. When the field is found, begin site preparation, determined by the specific conditions. So, if the kimberlite pipe is located deep under the ground, equipped with closed underground mines, as if at the bottom of the sea - are special robots. After preparing the construction site concentrator, which will deal with the extraction of diamonds from the rock.
The technology of the diamond consists of three stages. In a first step the ore is crushed and separated into diamond and kimberlite concomitant formation. This is done directly at the mine in the special installations.
In the second step the ore is crushed again, pure diamond kimberlite sorted into 4 categories depending on the particle size and release the diamonds from the accompanying rocks. This occurs at the factory.
Methods for separating the accompanying rock of diamonds.
The most primitive way - fat installation: on a table covered with grease supplied kimberlite mixed with water. Water carries associated rocks and diamonds adhere to the grease, they are collected.
More advanced electromagnetic system. Their action is based on the fact that diamonds are not attracted by magnets and related species is attracted strongly enough.
The X-ray machines ore isradiation, resulting in diamonds glow blue light. Special sensors, locking it glow actuated mechanism that cuts the diamonds from the accompanying rock.
When diamonds are separated from the accompanying rock, begins the third stage of treatment. Diamonds are sent to the sorting plant where they are collected and inspected for weight and diameter class.