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
I have the same issue! I tested it with a completely fresh game and without any mods. It happens with all kinds of metal except for Silver and two or three other very light ones. The crystals are not affected, but the metal part always appears to be red when the jewelry is worn by a sim (earrings in the pictures are Phozonite and Peach Crystal).