Scott Gleeson

USA TODAY Sports

Olympic medals for more than 130 winners from the Rio de Janeiro Games last summer are rusting or chipping, according to officials.

“We’re seeing problems with the covering on between 6 or 7% of the medals, and it seems to do with the difference in temperatures,” Rio Games communications officer Mario Andrada told reporters. He added that the decaying was “completely normal” after nine months, since only 1.34% of the medals are actually gold, and 30% of the sterling silver came from recycled silver.

"The most common issue is that they were dropped or mishandled, and the varnish has come off and they've rusted or gone black in the spot where they were damaged," Andrada said.

The International Olympic Committee and Rio organizers are planning a system to replace the medals for those who are unsatisfied with the defective medals, Andrada said.

At the London Olympic Games in 2012, organizers provided instructions to medalists on how to keep their medals in mint condition, but did not specify any detail on room temperature. Medals for each Olympics vary in how they are made, however. The Olympic medals for the 2020 Games in Tokyo, for instance, are expected to be composed of recycled cellphones and small appliances donated by Japanese citizens.

The news of the defective medals comes in light of many Olympic venues in Rio deteriorating quickly after the Games, with a federal prosecutor recently saying that the venues are “white elephants” that were built with “no planning” for usage after the Olympics.

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