This brief introduction will provide you with the basic knowledge you need to place and remove gems from ring settings. You'll learn what tools are needed, what the basic techniques are and what to watch out for when setting the gems.
Definitions
Table: The table of a stone is its cut flat top. This is also known as the face.
Girdle: The girdle on a stone is that edge that is formed where its top and bottom -- also known as the pavilion -- meet.
Setting: A ring or pendant that is designed to hold a faceted (cut) gemstone.
Preparing the Pieces
Make sure your gem is clean. Wiping it with a jeweler's cloth will remove any particles that may complicate the setting, or could cause damage to the setting,
Often, the notches in ring setting prongs will contain some debris or residue. Use the jeweler's file to clean out all notches, making certain there is nothing there that will impede a clean fitting.
If the prongs have no notches, you will have to create them with your file. Make the notches about 1/16th of an inch from the tip of the prong.
Sizing the Gem and Setting
Place the gem on a flat surface, with its table side down. (In other words, the gem will be "upside down" on the surface.)
Take the four-pronged setting and gently place it on the gem. Ideally, the setting should be slightly smaller than the gem. You're going to want the gem to "snap" into place in the notches when you apply a little pressure.
You may have to adjust the prongs so they will fit the gems. This is usually the case with larger (1 ct. or larger) stones.
To adjust the prongs, use the bent chain nose pliers. With the tip of the pliers near the base of the prong, grasp the prong lengthwise in the pliers and bend in, very slightly. Repeat this process for all four prongs.
After bending all four prongs in, place the setting on the gem. You want the setting to fall to just above -- from your perspective -- the girdle.
Setting the Stone
Using very slight pressure, push down with your thumb on the setting. The prongs should snap into place along the girdle.
When you pick up the setting, the gem should be set so its top is level, and it should not be easy to move.
Now, using the jeweler's pliers, bend the tips of the prongs so they cover part of the gem and lock it in place.
To lock the gem in place, position the setting so that one prong lies against the shorter of the pliers' jaws, and the top of the prong directly opposite is under the longer jaw. Press the handles together, and the pressure should bend the tip of the opposite prong down against the gem. Repeat this step with all prongs.
To make certain that the gem is set securely, use your bent chain nose pliers. Place the jaws of the pliers so that they are gripping two prongs on opposite sides of the gem and squeeze. Do the same with the remaining two prongs. The gem should be securely set in the ring.
Removing the Gem
Removing a gemstone is generally not recommended, unless you are a professional or have a lot of experience. If the prongs are weakened by constant bending, you could break them off completely.
To remove the gem, using the bent chain nose pliers, gently grip and bend back the prongs from the top of the gem.
Begin with the prong tips, then gently bend back the shaft of the prong until the gem is loose.
Tips
Be very gentle when bending the prongs. You probably won't damage the stone, but you could scratch the setting. if that happens, gently file the setting, and then polish with a jeweler's cloth.