jewellery shop

Zakaat on jewellery

Q:

1. A person has a jewellery shop. In this he sells a golden ring having a diamond. The gold value of the ring is 1000 pounds, but the ring is sold for 2000 pounds (which includes the value of the diamond, labour etc). Should he pay zakat on the gold value (1000 pounds) or the full value of the ring (2000 pounds)?

2. Further, the person buying the ring, should she pay zakat on the gold contents (1000 pounds) or the full value of the ring (2000 pounds)?