When designing/making any type of jewellery with the gold metal, the end product will appear more bronze/copper colour WHEN worn on a SIM, I know for a fact I'm not the only with this issues, someone...
Ideas
Мetals of yellow shades (gold, phozonite, ozinold) in finished jewelry look red on the character. In the luggage or in the world, these items have their usual color. Gold necklace, Phozonite earrings: