Making silver coins can be done in several ways, but the easiest method for the average backyard silversmith is to stamp melted bullion. Melting the silver into flat, round disks, then pressing them with an etched steel stamp is the classic procedure used by ancient civilizations to produce currency.
Braze the graphite mold briefly to dry it, as moisture can affect the silver.
Melt a half-ounce of silver in the melting dish, using the propane torch. The silver can be from any source, but should have a stamp of purity if testing equipment is not available. Usually, old coin currency from most nations is 90 percent silver, many items stamped "Sterling" are 92.5 percent silver, and bars or bullion can be as high as 99.9 percent pure. It is commonly accepted that it is extremely difficult to make the metal 100 percent silver, as impurities can have very high melting points.
Pour the molten silver into the open graphite mold. It will begin to harden immediately, and should be poured quickly. After a few moments, turn the mold over and tap out the silver. Dip it in water, or allow it to cool naturally. The silver will now be a round bullion disk, about one-eighth to one-sixth of an inch thick.
Place the disk into the stamp, then strike it hard with the hammer. Do not strike it twice, or a double image may result. The result should be a deep imprint of the chosen design.
It is also possible to stamp letters and numbers individually, if a steel whole-coin stamp cannot be obtained.
Do not handle hot silver, allow it to cool first.