When selling gold and silver-proof coins, it is essential to be able to differentiate between the two types of coins. Here are some ways to tell the difference: 1. Weight: Gold is much denser and heavier than silver, so gold coins weigh more than silver coins of the same size. 2. Color: Gold has a distinct yellow color, while silver is white or gray. Gold coins will have a bright, yellowish luster, while silver coins will have a more muted, white luster. 3. Purity: Gold coins are typically made from 22-karat or 24-karat gold, which is 91.7% to 99.9% pure. Silver coins, on the other hand, are usually made from .999 fine silver or a lower-purity silver alloy. 4. Inscriptions: Most gold and silver coins have inscriptions that indicate their weight, purity, and denomination. Check these inscriptions to determine whether the coin is made of gold or silver. 5. Magnet Test: Gold is not magnetic, while silver is slightly magnetic. This reliable method can be used by placing a strong magnet next to the coin. If the coin is attracted to the magnet, it is likely made of silver. 6. Acid Test: If you are still trying to decide whether a coin is made of gold or silver, you can perform an acid test. This involves applying a drop of nitric acid to the coin and observing the reaction. Gold will not react to the acid, while silver will respond by turning gray or black. By mastering the art of differentiating between gold and silver proof coins, you can ensure that you are selling these coins for their true value. So, remember to check the weight, color, purity, and inscriptions, and perform tests like the magnet test or acid test. This knowledge can be your key to a successful transaction.