For Your Staff:Selling Quality
Inspecting Three-Stone Rings
Knowing the key inspection points on a three-stone ring demonstrates
another aspect of quality in your shop
by Jeffrey Mathews
JA® Certified Master Bench Jeweler
Jeffrey Mathews Designs, Dallas, TX
Open any publication featuring jewelry and you'll find the three-stone
ring usually a large center stone flanked by two smaller matched
stones. Beyond this, three-stone rings vary as much as the shoes you buy.
Though it's a simple and classic design, the style, structure, gem material,
metal and finish present a lot to consider during an inspection. The features
of three-stone rings and those that signify quality are important to know,
whether quality-checking a new ring or taking one in for service.
Design Variations of Three-Stone Rings
Traditionally, three-stone rings feature prong-set, faceted gemstones
as the major design element. Designs may vary greatly based on the materials
used and the size and shape of the stones, but they exhibit these common
A. The center stone and setting.
B. The side stones, settings and positions.
C. The shank design and function.
Here are the signs of quality you should look for in these common design
The Center Stone
The center stone is level and securely set. It shouldn't sit so high
above the finger hole that it turns the ring or makes it cumbersome to wear.
The culet of the stone should not protrude into the finger hole.
For structural security, the angle of the center stone prongs should
be between 65° and 75° from the upper gallery and symmetrical from
each side. The lower gallery is the structural base and should be 0.75mm
to 1.50mm wide. The upper gallery is slightly wider than the lower gallery.
FYI: Parts of Three-Stone Rings
1. Upper Gallery Wires
2. Lower Gallery Wires
3. Center Stone Prongs
4. Side Stone Prongs
5. Ring Shank
6. Split Shank
The Side Stones
The side stones are arranged to maximize their appearance and minimize
the appearance of the settings. The relative size, height and angle of the
side stones form a pleasing transition from the center stone to the shank.
Where the stone contours align, the girdles may be set close together for
maximum view. Creatively fashioned prongs add a custom look.
A view from the top
of this ring shows an emerald-cut gemstone with tapered baguettes. The prong
styles are appropriate for linear cuts.
When the shapes of the three stones prevent them from being in close
contact, the side stones are set lower and angled to bring them closer to
the center. Viewed from the top, the center stone appears to overlap the
side stones. Be sure the stones are set securely and the prongs are matched,
symmetrical and well-finished. Side stones should be set at the same angle
and height as the center stone. Inspect all metal-to-metal junctions and
surfaces for a proper finish
The center stone appears
to overlap the side stones. The prong styles are appropriate for curved
and pointed cuts.
The shank design supports all three gems with a sound structure and
practical features. The shape of the shank (finger hole view) can keep a
top-heavy ring from turning on the finger or provide a comfortable cradle
for adjacent fingers. Split shanks create a lighter look and feel.
Split, curved-out shanks show less metal and are better for top-heavy
rings. Solid shanks can double as prongs or channels for setting.
|Turn the ring to inspect the sides for symmetry, adequate thickness
(typically not less than 1.5mm) and distinct finishes. Shanks may be tapered
for a beautiful transition to the stones or for function to keep
a top-heavy ring from rotating.
||There are three basic shank shapes and endless variations.|
Finally, look inside the finger hole: you should be able to easily read
the quality mark and manufacturer's mark. The base of the lower gallery
should be symmetrical and well-finished.
You can reach Jeffrey at his studio in Dallas, (972) 496-6042.
Illustrations by Lainie Mann
The JA Professional's Guide to Fine
Inspecting Three-Stone Rings
By Mark B. Mann
JA Director of Professional Certification
These features are essential to ensuring quality when inspecting a three-stone
A. The center and side stones are level and securely set.
B. The center stone is not so high from the finger hole that it turns
the ring or makes it uncomfortable to wear. The culet of the stone doesn't
protrude into the finger hole.
C. All prongs are shaped and tapered evenly.
D. For structural security, the angle of the prongs holding the center
stone is 65° to 75° from the lower gallery and symmetrical from
E. The side stones are angled from the center to maximize the overall
appearance of all stones in the ring.
F. The height and angle of the side stones form a pleasing transition
from the center stone to the shank. (Ring size can suggest the best position
of the side stones. Usually, the larger the ring size, the less the stones
will angle downward.)
G. All solder joints are complete and free of pits.
H. The distance between the upper and lower gallery wires are even and
proportionate to the overall ring.
I. The quality mark and manufacturer's mark are visible and easy to read.
J. The inside of the ring is flat, even and free of polish lines.
K. All metal junctions are free of excess solder; the detail is crisp,
polished and free of pits and tool marks.
Features Indicating Potential or Actual Problems
The center stone is not level. The culet protrudes into the finger hole.
The side stones are not symmetrical to the
The stones are "trapped" in the setting (see sidebar at right)
The ring shank is not symmetrical when viewed from the finger hole. The
ring shows wear at the side and bottom. The shank design is not symmetrical
on the side.
An important quality feature in a three-stone ring is that all stones
are properly seated in their prongs rather than being trapped between the
gallery (or seat) and bent prongs. Fitted, notched seats in the prongs ensure
the stones will remain level and secure in the settings. Set-prongs are
notched and the stone is level.
The prongs are notched and the stone is securely seated in them
The stone is trapped be-tween the upper gallery wire and the bent prong
Illustrations by Lainie Mann
© 1999 Jewelers of America
This information is required to pass the fourth level JA® Certified
Master Bench Jeweler of the JA® Bench Jeweler Certification program.
Installments previously published in Professional Jeweler are
now available in a countertop book titled The JA Professional's Guide to
Fine Jewelry Craftsmanship. To order a copy, call Jewelers of America Inc.
at (800) 223-0673.
Copyright © 1999 by Bond Communications.