My Dad used to buy a lot of gold when it was made available to him. He had a process that seemed complicated but as I never buy gold I don't use it.
First he'd figure the value an ounce per karat based on the price that day. If a karat was worth $10.00 then 14k was worth $140.00 per ounce Troy.
Then he broke down the value in penny weights. Weighed the ring or earrings our what ever to get the golds worth. Then it got hard. Was he buying for scrap or for resale.
If he bought for resale he paid what he considered a wholesale price. Often as not he'd sell on consignment and take a percentage.
If he bought for scrap he would often pay 2/3 the value that day. And then he'd read the market and follow the bubble. He looked at gold price speculating as gambling.
One day shortly before he died we talked of all the gold mania. He felt that the way people were speculating gold scrap on daily basis would eventually take the craft Gold Smiths right out of the market by pricing gold right out of reach.
But then he never saw a sustained gold price above $1000. 00 per ounce.
I keep no gold pieces in stock but I will build to order.
I only use gold supplied from H & S or @RioGrande . I don't have to refine it or prove it's karat value.
Now Pawnshops buy gold or silver only for scrap. They keep things for 7 days as the law requires in my area and then it goes to melt. It doesn't matter if it's Grandmothers spoons or your sister's gold broach.