Tiffany Style Wire Prongs

Lesson: Tiffany Style Prongs

Most commercial settings have a shoulder cut into the master which indicates where they think the stone will/should be set. Hold the stone up against the side of the setting to see where you want to set it. For prefab setting this will usually line up with the shoulder, but for handmade settings there is no shoulder. If the prongs are too long, cut off the excess then proceed.

When the stone is set, the girdle will take up 50% of the prong thickness.

Layout:

• Use plastic/nylon lined pliers to straighten the prongs without damaging or scratching them.
• Move the prongs to where they should be when they are set. When you lay the stone on top of the prongs, the girdle should cover 50% of the prong.
• You must have the prongs in their final position when cutting the notches otherwise the angles will not line up when you go to set the stone.
• Double check alignment of prongs, and adjust if needed.
• Take cup bur and round off the prong tips.
• Cupping the prongs at the beginning of the setting leaves less finishing for you at the end, and reduces the danger of messing the piece up after the stone is set.

Cutting the seat:

• To cut the notches at the correct height, you want to extend the curve of the tips around into a complete sphere in your mind.
• Divide this sphere into thirds, and cut into the bottom third.
• You can tip the cup bur onto the inside face of the prong when you are rounding off the tips, and that will mark the bottom of the sphere for you.
• You want to cut into the bottom third so that you have enough material when the stone is set.
• Using a hart bur, cut a notch into the prong about 20% of the way through.
• Make sure to use a light touch.
• Cut the prong that is facing up, and rotate the GRS so that you are always cutting in the same position.
• Cut so that the bur rotates away from you. This way if it slips it will hit the bench pin and not your prong.
• Use your thumb along the shaft of the bur to guide it.
• Tip the bur back to deepen the pavilion angle by cutting with the bottom part of the bur.

Setting the stone:

• Bring the prongs out so that the stone fits into the setting.
• You can bring the prongs out with a dapping punch or pliers.
• Place the stone in the setting. It should be resting in the notches.
• Pull the prongs closed with the pliers- lever them into place.
• Always work with opposite prongs while doing this.
• Then vector tighten the prongs fully.
• To vector tighten:
• Squeeze 2 adjacent prongs together.
• Repeat with the other 2 prongs.
• Straighten the prongs by squeezing 2 prongs together, one from each set above.
• This only works if there isn’t a spacer or gallery bar in between the prongs.