At present, diamond deposits have been discovered in 27 countries in the world, most of which are located in Africa, Russia, Australia and Canada. Africa: Southern Africa is the main diamond producing area in the world (South Africa, Namibia, Botswana, Zaire, Angola, etc.). ). The world's largest diamond placer is located in Namibia, southwest Africa, with an average selling price of over $300/carat, of which more than 95% is gem-grade. The world's largest Kimberlite Cone (Mwadui) is famous for its gem-grade diamonds, which is located in Tanzania. The first discovered primary diamond deposit in the world is Premier, where many world-famous big diamonds are produced, such as Cullinan (365 365,438+006 carats), Noble (999.2 carats) and Jonger (726 carats). Botswana is another important diamond producing area. Its diamond revenue accounts for more than 70% of the country's export revenue, and its output value has remained the first in the world from 65438 to 0999. African countries such as Zaire, Botswana, South Africa, Namibia, Angola, Tanzania, Sierra Leone (the gem grade accounts for more than 60%, and the average price is 173 USD/carat) and Ghana have 56% of the total diamond reserves in the world, with an average gem grade of 3 1%. (2) Australia: 1979 The first discovery of diamonds in Australia's K-Mg lamprophyre is a breakthrough in diamond deposit science. Later, lamprophyres with a size of more than 150 K-Mg were discovered in the northern part of Western Australia, including a certain number of bright roses, pink and a small amount of blue diamonds. They are rare treasures, with an average selling price as high as $3,000/carat and high purity. Arghe is the rock mass with the richest diamonds and the largest reserves in the world. Australia is currently the country with the largest diamond production, accounting for 26% of the world's reserves, of which about 5% are gem-grade. ③ Russia: mainly distributed in kimberlite in Yakutia, Siberia. Although the particles are small, they are much more transparent. (4) Canada: 1990 The kimberlite-type primary ore discovered in the lake area near the Arctic Circle in northwest Canada is another breakthrough in the world diamond history, and it also poses a threat to De Beer's monopoly. ⑤ Asia and China: India is the first place to find diamonds in the world, producing ancient famous big diamonds such as Mughal the Great, Regent and Beatrix Wilhelmina Armgard, but the output is very low at present. The diamond placer with economic value was first discovered in Yuanjiang Valley, Hunan Province in China on 1950. The quality is good, and the gem grade is 40%, but the grade is low and scattered. The primary diamond mine discovered in Mengyin, Shandong Province in 1960s has high grade and large reserves, but poor quality. Gemstone grade accounts for about 12%, with yellowish color, which is mostly used in industry. In the early 1970s, a primary diamond deposit was discovered in Wafangdian, Liaoning Province, with large reserves and good quality, accounting for about 50% of the gem grade. It is the largest primary diamond mine in China and even in Asia (with an annual mining capacity of more than 654.38 million carats). At present, the largest one weighs 65 carats, and the average price of diamonds per carat is 120 dollars, while the price of diamonds in Australia is only a few dollars. According to the latest data, the world's highest output ranks as Australia (40 million carats), Zaire (20 million carats), Botswana (6.5438+0.6 million carats), Russia (6.5438+0.2 million carats) and South Africa (9 million carats). These five countries account for 95% of the world output. In addition, Namibia and Angola are also important diamond producers. However, according to the output value, the ranking is (according to statistics in September 2000): diamond producing country unit: US$ 1 billion Botswana/KOOC-0/7.82 Russia/KOOC-0/6.25 South Africa 7.76 Angola 6./KOOC-0/8 Namibia 4.30 Canada 4.05 Congo (DRC) 3.96 Australia 3.67 Venezuela/KOOC-0/0.