Mexico 1935 50 Centavos

This coin represents a particularly bizarre episode in the history of Mexican coinage. In 1935, on account of fluctuations in the price of silver, a decision was made to strike this denomination in merely .420 fine (although they had not been produced at all since 1925, and the peso for that year was not so reduced). And strike them they did - to the tune of 130 million (60 million of which were were churned out in Philadelphis, Denver, and San Francisco, although all bore the Mexico City mint mark, so there's no way to tell where an individual specimen originated). Then, after just over a year in circulation, this gigantic mintage was summarily demonetised. The 50 centavos was then again struck (in much smaller annual quantities) in .720 fine once more from 1937 through 1945.