I bought 12 similar to this in Dali, Yunnan. They spanned centuries but they all had the same wear and the same dirt. They were all the Yun mint so it sort of fit. I didn't pay big money for them, 100 yuan for all. They are well made fakes. The dirt on them is a giveaway. I saw some certified ones there but they were 400 yuan for 3 coins. Which was the biggest scam?