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August 1998
For Your Staff:Selling Quality
Bezel-Setting Round Brilliant Stones
Knowing what to look for when inspecting and taking in bezel-set round
brilliants demonstrates an aspect of quality in your shop
by Mark B. Mann
Director of Professional Certification
Jewelers of America
This month we'll discuss seven essential points to consider when taking
in and/or inspecting bezel-set round brilliant stones.
1. The stone is tight and secure.
An important first step is to inspect, clean and inspect again, each
time checking for loose and/or damaged stones. Stones loosen for various
reasons; here are some of the most common:
- During the original setting process, a metal filing was trapped between
the stone and the bezel and it has dislodged.
- The original seat or bearing for the stone was cut too large; metal
was burnished over the stone to tighten it, but over time it has loosened.
- The bezel has "opened-up" through normal wear, loosening
the stone.
- The stone has loosened through excessive wear of the bezel, and the
bezel material is too thin to reburnish.
Following are three ways to check for loose stones. (In next month's
article, we'll discuss repairing bezels and tightening loose stones.)
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Jiggle Method
Install a reciprocating hammer hand-piece onto a bench jeweler's flexshaft
and operate at high speed. Place the jewelry against the flexible shaft
cover, near the hammer hand-piece. If the stone is loose, it will jiggle. |
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Bamboo Probe
Using the pointed end of a bamboo skewer (from the grocery store), push
on various parts of the stone to see whether it's loose. The bamboo is soft
and won't damage the stone. |
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Sticky Wax
Most bench jewelers pick up stones during setting by placing a type of
sprue wax (used in the casting process) or soft sticky wax on the end of
a small probe. Stick this wax to the top of a stone and determine whether
you can turn or move it. |
| Caution: If you find loose stones, check them very carefully for concealed
damage before trying to retighten them. If a stone was set in a bezel to
conceal a flaw or previous damage, the force required to push metal over
the unstable stone to tighten it may cause further damage. |
2. The stone is level and even. Simply check this
by eye.
3. The facet orientation is "square"with
the design.
 
4. The bezel wall is thick enough to hold the
stone securely. For stones up to one-third carat, the wall should be at
least 0.50mm; for stones up to 1.50 carats, it should be about 1.0mm; for
larger stones, it should be thicker.
5. The thickness of the bezel wall remaining after
cutting the stone's seat or bearing is at least 50% of the original width
of the metal.
 Ideally, the stone sits securely on a seat or bearing cut into the bezel.
The bench jeweler then folds metal over the stone to keep it in place. The
seat must be the same diameter as the stone; if it's cut larger and metal
is then folded over to keep it in place, the stone will loosen quickly.
This is an error in workmanship.
6. The thickness of the remaining bezel wall is
even and the wall is finished consistently and in full contact with the
stone. Because the bezel facets of the stones can "terminate"
differently (see box), it's difficult to determine whether the stone has
proper contact with the bezel.
 
7. The stone is not damaged. The facet junctions
are not abraded or scratched and there is no other damage to the stone.
Contributions for this article were made by JA Certified Master Bench
Jeweler Jeff Matthews of Jeffrey Howard, Dallas. TX.
Illustrations by Lainie Mann
JA Quality Assurance Guide
Bezel-Setting Round Brilliant Stones
 Proper Bezel Setting
of Round Brilliant Stones
- The stone is tight and secure.
- The stone is level and even.
- The facet orientation of the bezel is "square" with the design.
- The thickness of the bezel wall is sufficient to hold the stone securely.
- The top portion of the bezel is evenly burnished over the stone.
- The top of the bezel is bright-cut or finished evenly.
- The stone is not damaged.
Potential Problems When Bezel-Setting Round Brilliants
The stone is not level
If the stone is not level as shown (an error in workmanship), you must
remove it and reset it into a new bezel.
 
The portion of the top of the bezel holding
the stone is wavy and irregular
If the top of the bezel and the stone are not in full contact, the top
must be burnished to gain full contact.
The top of the bezel is unfinished, irregular
or thin
The top of the bezel should be of even thickness and finished (perhaps
bright cut).
 
Stone set too low
The table of a bezel-set stone should be slightly above the folded or
burnished edge of the top of the bezel. This one is set too low, an error
in workmanship.
illustrations by Lainie Mann
©1998 Jewelers of America
Standards as described by the JA® Bench Jewelers Certification Program
Copyright © 1998 by Bond Communications.
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