Olympians who take the traditional, iconic bite from their hard-won medals are actually biting down leftover car parts, mirror surfaces and X-ray plates.

Hailed as the most sustainable in Olympic history, the Rio medals feature 30 percent recycled materials. Even the ribbons from which the ultimate prizes hang from are made up of 50 percent recycled plastic bottles.

Possibly the heaviest medals in the history of the Summer Olympics, the 2,488 medals for the 2016 Olympics have a diameter of 85 millimeters, they weigh 500 grams and are slightly thicker at their central point compared with their edges.

They have been produced by the Mint of Brazil with "sustainability at their heart," the organizers said.

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The gold medals respect the strict guidelines of the International Olympic Committee. They are plated with six grams of gold with 99.9 percent purity. They boast gold extracted without the use of mercury.

The remaining 462 grams of the medal are silver with 92.5 percent purity, which is the a minimum IOC requirement, and the rest is copper.

In Rio, 30 percent of the sterling silver to make the gold and silver medals was obtained from recycled material such as X-ray plates, car parts and mirror surfaces. The copper used to create the bronze medal was recycled from discarded materials at the Mint itself.

As for the medals' design, it "celebrates the relationship between the strengths of Olympic heroes and the forces of nature," the organizers said.

On one side, symbolic laurel leaves from ancient Greece surround the Rio 2016 Olympic logo, on the other the focus is on Nike, the Greek goddess of victory with the Panathinaiko Stadium and the Acropolis in the background.



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