- 1). Find a setting with the correct number of prongs for your stone. The size and shape of your gemstone are used to figure out what kind of mount to use. If it is a princess, emerald or Asscher cut, a four-prong setting is generally used. For a round, oval or marquise stone, a six-prong setting is necessary. The placement of the prongs are also important and depend on the cut of the stone you want to mount.
- 2). Determine the size of the setting. A stone that is 8 by 8 mm will not fit securely if it is mounted in a setting that is larger or smaller. Measure your stone and obtain the appropriately sized setting. Also measure the height of the gemstone, because if it is too tall or too short for the prongs, you can't mount it correctly. Look for a pre-notched setting. This means that there are notches cut into the prongs, which will capture and hold the gemstone more securely.
- 3). Set the gemstone into the space in the center of the prongs. Ring mounts are generally unused and ready to drop a stone into the setting area. Using tweezers, carefully place the stone into the middle of the prongs. It may appear to fit well, but at this point, it is not secure yet.
- 4). Carefully crimp one prong at a time. Using needle-nose pliers or a jeweler's mounting tool, position the bottom tong of the open pliers at the bottom of the setting just below the prong you're tightening, and the other one at the top. Gently apply pressure and squeeze the pliers shut, causing the prong to bend over the top of the gemstone. Then repeat the process with the opposite prong. Continue, always crimping the prong that's diagonal from the first, until all the prongs are folded over the stone and it is set into the pre-notched areas of the mount.
- 5). Crimp the prongs, adding a bit more pressure every time, to fully secure the gemstone in the ring. Be careful not to overtighten the mounting, since some materials such as gold or silver can be easily damaged. The stone can also crack if you use too much pressure.
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