Members of Japan’s Olympic organising committee tabled the idea to government officials and companies earlier this year, local media reports said.
Olympic host cities have traditionally obtained the metal from mining firms. But Japan, which lacks its own mineral resources, is keen to take the theme of a sustainable future a step further.
The International Olympic Committee (IOC) has developed strict criteria for the world’s greatest sporting event, and this extends to how the medals should be produced. The Rio Olympics, for example, used gold that was extracted without the use of mercury and a third of the silver and bronze used came from recycled sources.
The amount of metal needed will depend on the size and number of medals, since each year, they seem to get bigger and heavier. Five new sports have also been added to the Tokyo 2020 competition, including baseball, karate, skateboarding, sport climbing and surfing.
The 2016 Rio Olympics had the largest medals of any games, weighing in at 500g each and 1cm thick in the middle.