I sell my scrap gold to Midwest Refineries http://www.midwestrefineries.com/
When I say scrap, that means the value of the actual gold content if it is melted down. It could be worth more as a piece of jewelry. The scrap or melt value would be the lowest amount you should get. Roughly, this is how Midwest calculates what they pay you. Take the troy ounces the ring weighs (less the weight of stone) then multiply that by 55% if 14K or multiply by 39% if it is 10k, then multiply the product by 95%, then multiply this product by the price per troy ounce of gold the day they receive it. This is the amount they will pay you for just the melt value. Example: If ring weighs .75 troy oz (after deducting for any stones) and it is 14k, and the troy oz. price of gold is $1,553.00. Multiply .75 times 55% times 95% times $1,553.00 equals $608.58, the amount they pay you. You can get the spot price of gold online at any point in time. If you don't have scales, you can take it to a jewelry store or pawn shop and have them weigh it. It is probably not 24k. Most rings are alloyed with another metal and are usually 10k 14k, or some 18k. 24k is pure gold and too soft for jewelry. If it is worth more as a piece of jewelry, you probably would not want to sell it as scrap.
Slow and steady wins the race.