The creation of white copper is an outstanding achievement in our contemporary metallurgical skills, which is called "Qi" in our contemporary era. "Old Tang Shu Yufuzhi" reads: "Take the white bronze calf car for the rest of the product." That is to say, the Tang Dynasty demarcated that as long as the cattle were pulled by a courtier, white bronze could be used as decoration, annotating that white bronze was quite precious in the Tang Dynasty. The white copper mentioned here should be nickel white copper rather than arsenic white copper. Because nickel white copper is anti-corruption and suitable for decorating cattle carts, arsenic white copper is not stable, and will droop into yellow when time is long because of arsenic volatilization. In contemporary Chinese literature, red copper alloys are collectively called white copper, which includes three kinds of copper alloys: one is copper-tin alloys with high tin content, such as "Daxia Zhenxing" copper coins (419-424) and Sui Wubaht coins, which are all high tin bronze without nickel. Another example is a collection of Chinese white bronze mirrors from Nara period (7th to 8th centuries) in Shiseikura, Japan, which contains about 25% tin and 5% lead, and is also high tin bronze. The second is copper-arsenic alloy containing more than 10% arsenic, i.e. arsenic white copper; and the third is copper-nickel alloy, i.e. nickel white copper. Among the three kinds of white copper, nickel white copper is the most important, followed by arsenic white copper. Yunnan people not only create and produce white copper in China, but also in the world, which is recognized by domestic and foreign academic circles. The five poisons of white copper cost money. In ancient times, the white copper produced in Yunnan was also the most famous, known as "Yunbai Copper". At the latest in the 4th century, Yunnan had a large number of copper mining and production. Copper and nickel symbiotic ores still exist in Huili of Yunnan Province, which provides material for the smelting of white copper. "Han Shu" records: "Qianwei County northeast Zhuti Mountain silver", and there is "Zhu Tiyin 82 for first-class (Wang Mang when the silver two units)" said. However, according to contemporary assessment, Zhu Tishan (now northeast of Yibin, Sichuan) produces copper and nickel but not silver, so "Zhu Tiyin" can be nickel white copper. The first white bronze record recognized in China (and in the world) can be found in Volume IV of Huayang Guozhi Nanzhong Zhi, Changbi, Eastern Jin Dynasty, in the 4th century A.D. The article records: "Mantis County because of mountain name, silver, lead, copper, miscellaneous drugs." Mantis County is located in the area of Qiaojialaodian Town, Yunnan Province. There are rich copper deposits here, while the neighbouring Sichuan Huili nickel deposits have similar posts between the two places. From the capital point of view, it can be determined that the white copper produced by Mantis County is nickel-white copper. This is the first reliable record of nickel and white copper. These historical records show that white copper was produced very early in Yunnan Province of China, but it was indirectly produced from copper and nickel-bearing ores at that time. Although China has a long history of smelting white copper, there is no pure metal nickel. The arsenic ore produced in Yunnan is now called "arsenic nickel ore" in mineralogy. In 1929, Wang Jian elucidated the chemical composition of a contemporary white bronze stationery in China, and confirmed that it contained 6.14% nickel, 62.5% copper and a large number of tin, zinc, iron and lead. The white copper devices manufactured in our country today are not only sold all over the country, but also exported to foreign countries. Textual research shows that as early as the Qin and Han Dynasties, in the Daxia kingdom in the west of Xinjiang, there were white copper forged spring coins containing 20% nickel, which could be elucidated from its shape, composition and historical premises at that time.During the Tang and Song Dynasties, Chinese nickel-white copper was sold to the Arab region. At that time, Persians called it "Chinese Stone". From the 16th century onwards, China's white copper has been sold all over the world and won widespread praise. It was imported from Guangzhou and sold to Europe by the British East India Company. The English word "Paktong" or "Petong" is the transliteration of "white copper" in Cantonese, which means white copper from China or copper-nickel alloy from Yunnan. There were more and more records of nickel and white copper in the Ming Dynasty. The origin of nickel and white copper annotated in the Ming Dynasty coincided with Yunnan and Sichuan provinces. Nickel-white copper has more and more detailed records in Qing Dynasty literature. During the Qing Dynasty, there were factories and mines specializing in white copper mining and workshops producing white copper wares in Yunnan. Shi Limei's Dian Series and the Continuation of Tongzhi Manuscript of Yunnan in Guangxu years both say that Dingyuan County (now Mouding County) has Damaoling Baitong Factory, Matai Baitong Factory, and Dayao County has Maosheng Baitongzi Factory. According to the relevant records in "Continuation of Tongzhi Manuscript of Yunnan", Maoling Baitong Copper Factory in Dinghongyuan may produce 20,000 to 34,000 Jin of white copper a year. In addition, Huili, Sichuan Province was also an important producer of nickel and white copper in the Qing Dynasty. There were Lima River, Jiudaogou, Qingshuihe and Lixi white copper mines. The Lixi white copper plant had the longest history and the largest scale. There were 216 smelters during the Qianlong period, with an annual output of about 37 tons of white copper. During the Jiaqing period of Qing Dynasty, Tan Zhui talked about the production environment of Yunnan Baitong Ware Workshop in Yu Heng Zhi of Yunnan Sea: "Baitong noodle basin is the world's largest in Yunnan system, and its stores are above the Four Brand Towers (the middle section of present Kunming Axiom Road). Futong comes from Yunnan, but the Yunnan craftsmen can't be big gongs and small gongs. They must buy from Jiangning. The Jiangning craftsmen are from the Baitong of Yunnan, and they can't be as good as Yunnan's noodle basin, because of the soil and water. There are a lot of white copper utensils, although good is not unique, but unique only face basin, which is considered expensive at home. The Yunnan white copper basin mentioned here can't afford dirt. The new features of the basin can be called a Qing white copper warming pot as one of the best in China. For the smelting techniques of nickel white copper, the literature is very ambiguous. Discussions and annotations on the relics of contemporary nickel-white copper smelting in Huili Lima River, Xiaoguanhe River, Lixi and Qingming Mine, Sichuan Province, show that the temperature of contemporary nickel-white copper smelting is 1300 ~1400 C, the process is abnormally simple and needs repeated calcination and smelting; the reality of white copper smelted by Huili is Copper-Nickel-Zinc binary alloy, while Yunnan white copper is copper ternary alloy, which is matched with Huili white copper. Smelting of copper, zinc and brass. As nickel white copper is usually distributed in Kunming and Huize of Yunnan Province, and then sold in other provinces or imported, it is known as "Yunnan white copper" in the world.