900 Cash - Wang Mang Third reform

Wang Mang's monetary reforms were among the most ambitious — and catastrophically unpopular — currency experiments in Chinese history. His third reform in 10 AD introduced a bewildering array of new denominations designed to replace Han coinage, but the artificial valuations bore no relation to metal content, and the population largely refused to use them. Counterfeiting was so widespread that Wang Mang made currency fraud a capital offense, yet also decreed that anyone who informed on a counterfeiter would receive the counterfeit coins as reward — an almost self-defeating policy.

The 900-cash valuation on a coin of this weight tells the whole story of why the reform collapsed within years.