Usually, jewellery manufacturers use brass metal to make artificial jewellery.
Yes, Because of Gold jewelry is made up of the combination of Metal. Gold jewelry can be created with Silver, Copper, Zinc, Nickel etc. To create various colors. Most common color of gold jewelry is the Yellow, White, Rose and Green. Yellow Gold is made up of pure Yellow, Copper, Silver and last but not a least is Zink. So Zink is always used to making a Gold jewelry.
Zinc is used for making jewelry although very rarely.
Have a look at some jewelry collection made up of zinc alloy:
Have a look at some jewelry collection made up of zinc alloy: