Your gold may be of a lower grade than you think.
Gold items, such as coins, watches, necklaces, brooches and earrings can fall within a wide range of purities. While a jeweler or manufacturer may place a karat stamp on your item, it may be of a lower purity grade or mixed with other types of metals. Two inexpensive methods can be used at home to test the purity of your item. Purchasing these testing items in kits meant specifically for this purpose is the safest way to test your own gold at home.
Instructions
1. Place your gold near the high-strength magnet. If the magnet attracts the gold easily, it is of a low purity and mixed with other metals. There is no need to continue testing.
2. Spread newspaper out on a flat workspace. Put on rubber gloves and goggles.
3. Rub your gold firmly but carefully across the black stone until it leaves a streak.
4. Place a drop of nitric acid on the streak with your dropper. If the color doesn't change at all, your gold is of a high purity. If it changes only a little, it is of a medium purity. If the color changes drastically, the gold is of a very low purity.