The earth's land area is about 140 million square kilometers, while the diamond-bearing kimberlite tube has an average surface area of ​​only 0.05 square kilometers. To get 1 carat (0.2 g) of polished diamonds, you need to excavate 250 tons of ore.
Formed hundreds of millions of years ago
The diamond was formed hundreds of millions of years ago, buried deep under the seabed tens of thousands of meters, subjected to high temperature and high pressure, and then crystallization after thousands of times, and finally rose to the ground with the help of volcanic eruptions, to reveal the brilliance. It is precisely because the diamonds have remained radiant for hundreds of millions of years, thus earning the reputation of “eternal†and becoming the symbol of today’s “lasting true loveâ€.
The number of diamond deposits is small and the grade is low, and the grade of gem-quality diamond deposits is lower. The earth's land area is about 140 million square kilometers, while the diamond-containing kimberlite tube has an average surface area of ​​only 0.05 square kilometers. Of the diamonds mined, on average only 20% reach the gem level, while the remaining 80% can only be used in industry. A rough statistic found that to get 1 carat (0.2 g) of polished diamonds, about 250 tons of ore need to be excavated.
The exploration and mining of diamond deposits is difficult and costly. Since diamond-bearing kimberlite and potassium-magnesium lamprophyre are extremely rare on the Earth's surface, finding diamond deposits is a time-consuming, costly and risky investment. For example, the exploration of the original Siberian diamond deposit in the Soviet Union was discovered after 18 years of hardship. In the process of mining, diamonds need to fully exploit the ore containing diamonds, and be careful to ensure that the rough diamond particles in the ore are intact.
Diamond processing procedures are complex and the amount of work is large. Diamond processing goes through a series of steps: crushing, sorting, designing markings, boring, sawing, car drilling, grinding, and cleaning. And every step also includes a lot of small programs. Every small step requires exquisite craftsmanship and rich experience.
Diamond is the only gemstone that combines high hardness, strong refractive index and high dispersion. Some people have preliminary statistics that a diamond is involved in the mining, sorting, processing, grading, sales, and finally sold to the purchaser, involving more than 2 million people. A diamond ring is the crystallization of natural creators and more than 2 million people. The preciousness of diamonds is also here.
Most of the reserves are in Africa
At present, diamond deposits are found in more than 40 countries around the world, with Africa accounting for the most. The world's proven diamond reserves are about 3 billion carats, with reserves of nearly 1.1 billion carats in Central Africa, accounting for 35% of the world's diamond reserves; about 600 million carats in southern Africa, accounting for 20% of the world's diamond reserves; about 300 million carats in West Africa , accounting for 10% of the world's diamond reserves. The world now mines about 90 million to 100 million carats a year, and Africa produces more than half of the world's diamonds. The countries where African diamonds are produced are mainly concentrated in the Democratic Republic of the Congo (DRC), Botswana, South Africa, Angola and Namibia. Botswana's rough diamond production accounts for 25% of global production, South Africa accounts for 7.5%, and Congo (gold) accounts for 3.5%.
The diamond mines in Africa are mainly sand deposits and kimberlite primary deposits. In general, diamonds produced in African countries account for a large proportion of gem-quality diamonds. The diamonds have larger particles and better quality. For example, more than 95% of the diamonds produced in Namibia’s “Gold Coast†are gem-quality; Botswana gemstones The level of diamonds reaches 50%, and the South African Premier Mill is recognized as a giant diamond producing area.
Although the reserves of African diamonds are large, the annual amount of mining is also large, and it is only 30 years of mining at current annual production and speed. However, with the search and discovery of new mines, the outlook is still very optimistic.
The international standard for measuring diamond quality is not the place of origin, because existing instruments and equipment are difficult to distinguish the origin of a diamond. The measure of diamonds is 4C, which considers the four factors of weight, cut, color and clarity of the diamond.
Following the 6th century "Antwerp cutting"
Most of the diamonds are stored in Africa, but the best processing is not here. As the “World Diamond Processing and Trade Centerâ€, Antwerp in Belgium processes nearly 50% of the world's diamonds a year.
A diamond is the most radiant, and a superb cut is crucial. In the field of diamond cutting, the Belgian craft is perfect. First of all, only 50% of the original diamond will be selected for cutting; the next type of design often takes a lot of patience to develop the cutting plan; then it is to split the rough stone on the diamond sawing machine, divide the diamond into several petals or remove the diamond. The edges and corners, then on the diamond lathe according to the design requirements, the diamond into a variety of shapes; after the first three steps, the diamond only has a preliminary shape, no facet, no light, the next is to polish the diamond, according to The material of this diamond is polished to a number of facets. At this time, every facet polished must have scientific symmetry, let the diamond shine the most. Of course, if the operation is not done properly during the polishing process, the high temperature may cause a valuable diamond to be instantly turned into a powder. It takes at least two days to polish a high-quality cut diamond, and it takes months or even a year to polish a large carat diamond.
The world-famous "Antwerp Cutting" has been used for 6 centuries, and the shape cut out is 32 faces and 32 faces. This is the most transparent standard for diamonds. It is said that a diamond weighing 10 carats is only half left after cutting in Antwerp, and the remaining 50% is powdered.
Into the workroom of the Antwerp Diamond Appraisal Center, the rows of workbench are all kinds of instruments and computers, the working atmosphere is very quiet, the appraisers use a variety of beamsplitters, optical microscopes, electron microscopes, lasers, according to the steps Check the quality of the diamonds in turn. All diamond inspection data will be stored in the Diamond Identification Center's computer server for 10 years for customers to query via the Internet.
Women's Jacket,Lady's Coat,Lady's Jacket,Women's Coat
zhejiang tianjin import and export co.,ltd. , https://www.tianjintextile.com