Counterfeit coins and bills are hard to make and with the advancement of technology, hard to pass for genuine money. Store clerks are armed with a variety of techniques, from special pens to knowledge of watermark placement, making it even more difficult for those looking for undeserved cash to score big.
However, with the proliferation of vending machines across Japan and the circulation of a high-value 500 yen (US$5) coin, counterfeiters have a perfect mark for cashing in their fake coins, as a recent photo on Twitter confirms.