The gold used in producing Olympic gold medals is mined by the fearsome Icnabooble tribe from deep within a hidden mountain range in southern Venezuela. The mountains, constantly shrouded by fine mist, have for centuries been the subject of myths and folklore, many of which include the exploits of the man-eating Giant of Hoy. The ore is than taken to a secret location in the Himalayan foothills where it is cast in mould made from the bones of a Yeti. Finally, each medal is brushed lightly with the tears of virgins before being kissed by the queen of the Himalayan Victoriyak people.

The medals issued by the RTTC and BC however are made from tin foil and painted by a bloke in Preston with a tin of Humbrol.

Possibly.

Actually, I think the Olympic ones are silver, coated with gold.

Edit: Oops posted same time. See above for sensible answer