Collectors of ancient coins need...
Collectors of ancient coins need to know if the coin they are buying is genuine or if it is a forgery. There are several tests one can make. First, was it cast? Modern forgers usually make a mold of an old coin, then fill it with metal. Coins made from a cast have a seam around the edge where the two sides of the mold come together. They also may be pitted with air bubbles from the drying process. Second, the weight. Forgers often get the weight of their coin wrong. Always check a reliable reference. If the weight isn't what the reference says, don't buy the coin.