Kaiyuan Bao Tong is a kind of copper coin cast in the Tang Dynasty, with the word "Bao Tong" on it. In the early Tang Dynasty, the use of Sui five baht was easy and confusing. In the fourth year of Wude in Tang Gaozu (AD 62 1 year), in order to rectify the chaotic monetary system, waste Sui money, imitate the strict norms of five baht in the Western Han Dynasty, and start casting "Kaiyuan Bao Tong" to replace the remaining five baht in society.
"Old Tang Book: Records of Food Goods" records: "(Tang) Emperor Gaozu acceded to the throne, still using the Sui Dynasty five baht. In July of the fourth year of Wude (AD 62 1 year), five baht was spent, and the money was used for Kaiyuan Bao Tong, with a diameter of eight cents and a weight of two baht and four baht. Ten products weigh one or two, and a thousand products weigh six pounds and four ounces. " Qian Wen was inscribed with "Kai Jian" by calligrapher Ou Yangxun, and his form still follows Qian.
Kaiyuan Bao Tong was the first currency in the Tang Dynasty. Because of its reasonable quality, proper currency control and exquisite craftsmanship, it is deeply loved by the people. Kaiyuan Bao Tong has become a part of the Five Emperors' Money, which has the effect of exorcising evil spirits and attracting wealth.
Kaiyuan Bao Tong casting
In terms of quality, in general, Kaiyuan Bao Tong weighs one yuan and one article, ten articles and one article, and six kilograms and four articles (that is, one thousand articles). Each item weighs 2 baht 4 ounces, which is equivalent to a mass of about 4.2 grams. However, during the Kaiyuan period of Emperor Xuanzong of the Tang Dynasty, the copper materials in Kaiyuan Bao Tong increased by one to twenty percent. At this time, the mass of Kaiyuan Bao Tong was about 4.5 grams to 5 grams, so most of the cast Kaiyuan Bao Tong was heavier.
From the style point of view, Bao Tong had a bare back in the early Tang Dynasty, and the back of Qian was decorated with stars and the moon in the middle Tang Dynasty. At the end of the Tang Dynasty, Huichang Kaiyuan added the name of the Money Bureau to the back of the money. After more than 300 years of casting, the version is complex, and there are still castings after the Tang Dynasty, but the styles are mostly different from those of the Tang Dynasty. In terms of specifications, Kaiyuan Bao Tong was basically a small flat money, but in the Tang Dynasty, a small amount of "Kaiyuan Bao Tong" was also cast, which was converted into