Gold is a mineral found in the ground on both Planet Earth, Yuria and Mobius. Seen as extremely valuable, it is collected from mines and either sold or made into equally valuable items. Mobius is littered with the material in the form of the many Power Rings, although these are now largely obsolete. It has been suggested that the planet's primary source of this gold is from the Forest Hills Zone, an area famed for its high gold content. Because of this, Doctor Robotnik sent lackey Kid Cruel to kidnap the children of the Zone and force them to collect gold for him.
Elsewhere, bees from The Hive are the only known creatures in any universe to know how to create gold. The workers are regularly sent out into the dimension to search for the "ingredients", which are then brought back and turned into solid gold. It explains the enormous wealth of Charmy Bee and his family. Outside of the Sonic universe, gold is often fused with the enchanted metal of Hammerynth to provide powerful weapons like the Golden Axe.