RainbowKid
73. Well if it's copper, it's definitely going to tarnish. The US pennies are copper and do the same thing.
Paris Olympics winner showed off his tarnished medal after just one week of winning. American skater Nyjah Huston won a bronze medal and found his medal faded and looked like a decade old war medal.
The IOC regulated the quality of bronze medal to be 97% copper. Copper can be easily stained by oil and sweat from the skin, so a good old copper varnish should clean up. Or simply mail order a new one from China.