Compiled from Origins of Chinese Tea and Wine
In the olden days, tea was traded for horses. During the early years of the Song Dynasty, people from the inner regions used to purchase horses from the minority races with copper coins. However, the herdsmen forged weapons with the copper coins instead. In order to protect the borders, the Song government traded tea, fabrics and medicine with the herdsmen. They even appointed a ‘tea minister’ to regulate the supply of tea. During the Ming Dynasty, a good horse could fetch at most 120 jin* of tea, while an average horse was worth about 40 jin.
*One jin is approximately half a kilogram.