Historically, the diamond mining in Yuanjiang, Hunan Province can be traced back to the Ming Dynasty, known as octagonal. The Yuanjiang Valley in Hunan Province is rich in diamonds, which have the advantages of high quality, strong luster, large particle size and high gem grade ratio. Yuanjiang, Hunan Province is one of the three major diamond producing areas in China, with gem-grade diamonds accounting for 80% to 90%. Gem-grade diamonds are mainly concentrated in Yuanjiang River Basin, and their reserves are estimated to be 6,543,800 carats.