Well, at Cartier you pay $1.500 for the brand name already.
Btw. jewelery made from 24k gold is not such a good idea. Pure gold is very soft and scratches and bends very easily. Thats why nobody uses it for jewelery - not because of the higher price. A ring out of 24k gold is not gonna last a minute, if you apply a firm grip with that hand. You can bend it back into shape, but that sucks somehow, doesn't it.