Gold jewelry and coins are usually not pure gold. Because pure gold is very soft, another metal is added to harden these items and prevent damage. If you want to sell gold jewelry or coins for scrap, you have to find the proportion of actual gold in them before you can calculate the value. The proportion of gold is measured in karats. One karat is equal to 1/24 part gold. For example, 18K gold scrap is 18/24, or 75 percent, real gold. Look for a karat mark on the item. If there is none, take the scrap to a jeweler or assay service that can test for the gold content.
Valuing Scrap Gold
Once you know how much gold is in your scrap, look up the current market price of gold. Called the spot price, this information is available on many financial websites. Gold prices are reported in dollars per Troy ounce. There are 31.1 grams per Troy ounce, so divide the spot price by 31.1 to find the price per gram of gold. Multiply the price per gram of gold by the karat proportion of the scrap gold to find its price per gram. Suppose the spot price works out to $40 per gram and the scrap is 18K gold. Multiply $40 times 18/24 for a price per gram of $30.