Professional Jeweler Archive: Bead Setting, French Style

May 2002

Professional Bench/Defining Quality

Bead Setting, French Style

Knowing how to accomplish this skill demonstrates another aspect of quality in your shop

At Underwood’s, we take a team approach to every custom design. An original design typically starts with a sketch and general specifications. This one is for a tanzanite, diamond and platinum pendant.

With a rough sketch the concept is in place, but the overall design is incomplete. Among the detail I need to consider is how to set the 1.3mm diamonds in the platinum skirt surrounding the center stone. The best choice – French bead setting – uses only two prongs to set the diamonds close together, producing an appearance I call a “ribbon of light.”

The techniques used in four-bead and bright-cut setting are similar (Professional Jeweler, July 2000, pp. 138 –140). This article highlights the similarities and concentrates on the differences.

The Layout Procedure

First lay out the diamonds and indicate where they’ll be set. For standard bead setting, diamonds are spaced evenly by half their diameter. French bead setting differs, with spacing between the diamonds very close. I mildly heat the area where I’ll set the diamonds and melt a thin layer of boxing wax onto it. Then I set the diamonds face down and calibrate the spacing. When the diamonds are removed, the impressions of the diamonds’ tables are left in the wax. Mark the center of the tables for drilling pilot holes.

Seating the Diamond Melee

Seat cutting for four-prong and French bead setting is the same:

A. Drill the pilot holes 50% of the diamond’s diameter.
B. Flare each pilot hole using a bud bur to 90% of the diamond’s diameter.
C. Prepare a bearing or seat for the diamond using a setting bur that measures the diamond diameter or slightly smaller.
D. The depth of the bearing should allow the diamond’s table to be even with the height of the metal.
E. Azure the underside of the pilot hole to remove flashing.

Framing the Diamonds

Cut a frame line next to the seats using a narrow (#0 or #1) knife edge or an onglette (#000 or #00) graver. While cutting, lean or rotate the graver tip toward the outside edge. The line will extend just inside the seats, and the depth of the cut will be equal to the depth of the seats.
Once the framing is complete, you easily see that positioning the stones so closely together leaves very little metal to use as prongs. Notice the small upper and lower triangles of metal that form hourglass shapes between the seats. In normal four-prong, box-style bead setting, these triangles are large enough to split into two prongs. In French bead setting, however, these triangles of metal are small and each will become a single prong.

Isolating the Beads, Opposing-Prong Method

Isolate the beads using the opposing-bead method. Each diamond will be held in place by two beads diagonally positioned to each other.

To isolate the beads, use your narrow (#50 to #52) round graver to cut between the top and bottom of the hourglass. This isolation cut should be as deep as the seats.

Isolating the Beads, Shared-Prong Method

Using the shared-prong method, each triangle of metal will hold adjacent melee.

Use a narrow (#36 to #38) flat graver to cut a path down the center of the seats. This isolation cut, as deep as the seats, will be easy to accomplish because the metal is very thin here. Once you’ve isolated the beads, recut the seats with a setting bur. Don’t make them wider or deeper but remove the metal fins left from the graver work. Thoroughly clean the mounting.

Seating the Stones

Fit the stones into their seats, making sure each seat is level and cut to the proper depth. I use a brass pusher with a concave tip to push the stones into their seats. A small amount of sticky (boxing) wax will hold the stone in place. You’ll obtain the best final setting results with a tightly seated diamond.

Raising Beads, Opposing-Prong Method

These beads are small so care must be taken not to cut them off. Set the tip of a narrow round graver at the base of the prong, push it lightly into the prong’s base and then use the graver as a fulcrum to roll the prong onto the stone.

Raising Beads, Shared-Prong Method

I wax the melee in place and then use a narrow flat graver to raise the beads. Place the graver at the base of the shared prong, push it into the prong’s base and roll the bead over the junction of the two diamonds.

Finishing the Setting

After the diamonds have been set, shape the prongs with the correct size beading tool. One too small will form only the top of a bead; one too large will mash it and cut indentations on its sides.

Bright cut the frame walls using a flat graver, and remove any flashing around the beads. The edges of the frame walls are traditionally millgrained.

This information is required for the fourth level of the JA® Bench Jeweler Certification™ program.

By Tom Weishaar, JA® Certified Master Bench Jeweler™, Shop Manager, Underwood’s Fine Jewelry, Fayetteville, AR

The Completed Custom Piece

The Underwood design team designed this tanzanite, platinum and diamond pendant. The completed piece was entered in American Gem Trade Association’s Spectrum 2002 design competition and won Platinum Honors, Business Division, from the Platinum Guild International.

The JA® Professional’s Guide to Fine Jewelry Craftsmanship

Bead Setting, French Style

French Bead-Set Melee Diamonds

A. The beads are nicely formed, evenly spaced and sized, and they secure the diamonds.

B. The tables of all the diamonds are at the same height and are even with the rim of metal into which they are set.

C. The bright cuts are smooth, at about a 45° angle and are highly polished.

D. The millgrained edges are even and smooth.

E. All diamonds are free of chips or abrasions resulting from the setting process.

Potential problems to watch for

The tables of the diamonds are at different heights and are higher than the rim of metal into which they are set.
There is unformed metal at the base of the beads. The isolation cuts are not deep enough and the bead forming is sloppy.
The beads are differently sized and unevenly placed between the diamonds.
The bright cuts have indentations and excessive tool marks.

By Mark B. Mann, Director of Trade programs, Jewelers of America

This information is required for the first level of the JA® Bench Jeweler Certification™ program.

For more information about bench jeweler certification, call Jewelers of America at (800) 223-0673 or visit

© 2002 Jewelers of America
Illustrations by Lainie Mann – Visual Communications

Copyright © 2002 by Bond Communications