 Generally the cash produced by the Yining Mint were of the same weight and size as found in the rest of China and also used the same alloys, but the copper content of Yining cash coins was occasionally higher and the weight of these coins often exceeded the national standard and could weigh more than 5 grams.In the year 1776 a large amount of copper ore was discovered in the proximity of Yining city leading to an increased output of the Yining Mint.As the Qianlong Emperor ordered in 1775 that 20% of all cash coins cast in Xinjiang should bear the inscription "Qianlong Tongbao" even after the end of his reign as an "eternal reminder" of the Manchu conquest of the region, for this reason the majority of "red cash coins" with this inscription were actually produced after the Qianlong era as their production lasted until the fall of the Qing dynasty in 1911 making many of them hard to attribute.