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How to Buy a
Gem
It’s reasonable
to expect lasting value and enjoyment when you purchase gemstone
jewelry. Learning a few things about gemstone quality and value
will help you make sure you get what you want – and
deserve. You can start by
trusting your instincts. Sensory appeal is always paramount. So, if
a particular gem or jewelry design “speaks” to you, by all means
listen! You can also use what you know about the 4Cs. The
familiar diamond value factors of color, cut, clarity, and carat
weight apply to colored gems as well. However, each gem variety is
judged by its own potential: no one expects an aquamarine to have
the same color as a sapphire or an emerald to be as flawless as an
aquamarine. But there are a few general rules you can use to judge
gemstone quality.
Color Cut Clarity Carat
Weight The Perfect
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How to Buy a Gem:
Color Every
gem has a unique range of colors. Generally speaking, the purest
and most vivid color a gem can have will also be the most
expensive. But to really explain gem color, we need to look at the
three factors that define any color. |
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The first is hue, which is what we
normally regard as color: for example, a gem's hue will be red,
orange, yellow, green, blue, or purple, or it might be in-between
two hues: an orangey red or a reddish orange. For most gem
varieties, a pure hue is most favored. Gems with a pure red, blue,
or green hue are generally the most favored of all. |
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The second factor is saturation, the
intensity of the color. This is the tricky one to picture. Colors
that lack intensity often appear faded or washed out or look as
though the hue is mixed with gray or brown. A fire engine red is
highly saturated, a brick red less so. In gemstone color, more
saturation is always better. |
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The third factor is tone, the
lightness of darkness of the color. Pink has a light tone and
maroon has a dark tone. In gems, a medium tone, not too light but
not too dark, is considered best. Too light, and a gem's color is
too pale to be attractive. Too dark, and a gem isn't able to
sparkle with light. |
A gem's color is evaluated for
hue, saturation and tone. For example, the best rubies have a vivid
pure red color in a medium tone, with no modifying purple, orange,
or brown. But each gem variety is judged on
its own terms. For example, aquamarine always has a fairly light
tone but its lightness is part of its watery appeal. Gems like
orange-pink Padparadscha sapphire or blue green Paraiba tourmaline
are so beautiful, they make gem dealers forget that pure hues are
supposed to be better than mixed ones. These gems sell for premium
prices simply because almost everyone finds them beautiful. So feel
free to follow your own taste. Return
to Top > |
How to
Buy a Gem: Cut Next
to color, cut is the most important factor in beauty. Faceted
gemstones should have a pleasing shape with a lively display of
color and light. The flashes of brilliance a beautiful gem displays
are thanks to the skill of the cutter, who selects just the right
orientation and angles and proportions to maximize a gem’s
appeal. How can you tell if a gem is well
cut? First, it should display brilliance and scintillation evenly
across the face of the gem. Unlike diamonds, there is no “ideal”
set of proportions for cut: since each variety is different
optically, it requires different angles and ratios to look its
best. |
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Move the gem around and see how it
handles light. There shouldn’t be any dark lifeless areas or flat
washed out zones: light should be reflected consistently back to
the eye. Poorly cut gems may have a window: a non-sparkling area in
the center where light just shines through the back instead of
being reflected back to dazzle your eye. You’ll find that close
observation will reveal whether a gem dances with light or just
sits there. |
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All natural gemstones have characteristic
inclusions that form along with the gem in the earth. These
inclusions may be crystals, needles, voids, fissures, or even tiny
pockets of liquid trapped inside. If they don’t detract from
appearance, clarity features are accepted in most colored gems and
don’t affect value. In fact, they provide a benefit by proving that
the gem is natural. Still, the ideal for most gems is
that there should be no inclusions readily visible with the naked
eye, particularly if the gem has a light color. There are some
gemstones that are extremely rare without visible inclusions. You
should expect to see inclusions in emerald, red tourmaline, and, to
a lesser extent, ruby. |
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Most colored gems are available in a
wide range of sizes, but for some the selection is limited. Gems
are generally sold by weight, using the carat, which is one-fifth
of a gram. Some gem varieties are more dense than others: a one
carat emerald will be noticeably larger in size than a one-carat
sapphire or ruby. In general, the larger the gem, the more
expensive it will be per
carat. For the classic gems like ruby,
emerald, and sapphire, prices per carat can increase dramatically
as sizes increase. For example, since large ruby is very rare, a
three-carat ruby might be three times the price per carat of a
one-carat ruby, or nine times the total price. Some gems are much more available
in large sizes so the price doesn't rise as much as the size goes
up. Amethyst, Citrine, Aquamarine, Tanzanite, and Tourmaline might
have similar prices per carat for a one-carat and a ten-carat
stone; although the ten-carat stone will, of course, still be ten
times the price. |
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Both sides of the equation of supply
and demand come into play. Alexandrite, rare but in demand from
collectors, may cost as much as better-known gems. Some gems are
relatively rare but since they aren’t well known, there is little
demand, keeping prices low. The ancient world couldn’t tell ruby
and spinel apart, but spinel’s role as an unknown understudy keeps
its price relatively low today even though a one-carat red spinel
is more rare than a one-carat ruby. Other rare gems that are
relatively affordable include tsavorite garnet, morganite, red
beryl, and zircon. |
Within each gem variety, quality
determines cost. But different gem varieties have different pricing
structures. In general, classic ruby, blue sapphire, and emerald
are the most expensive gemstones. One level below these are the
rare collector’s gems like alexandrite, demantoid garnet, Paraiba
tourmaline, black opal, pink topaz, jadeite, chrysoberyl cat’s eye,
fancy sapphire and South Sea cultured pearls. The moderate price
range includes tanzanite, tsavorite garnet, tourmaline, red spinel,
aquamarine, precious topaz, spessartite garnet, and Tahitian
cultured pearls. Affordable gemstones include amethyst, citrine,
spinel, many colors of garnet, blue topaz, chrome diopside, fire
opal, white opal, iolite, kuzite, peridot, coral, turquoise, lapis
lazuli, chalcedony, and freshwater and saltwater cultured
pearls. |
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The creativity and craftsmanship that
go into fashioning gems and making jewelry also affect the value of
the finished product. Besides being beautiful, an exquisite gem
reflects the union of aesthetics, science, and technical mastery.
Fine jewelry combines gems and precious metal with talented design,
skilled execution, and attention to even the smallest
details. Value isn't a deep or complex
mystery. However, it simply makes sense to have the guidance of a
professional you trust when you purchase your colored gemstone
jewelry. Jewelry retailers who are AGTA
members are gemstone professionals who can show you how to judge a
gemstone's quality. Their stores carry a wide selection of classic
and unusual gemstones. They have the knowledge and training to give
you good advice about choosing gems and pearls, with full
disclosure of all the facts that are needed to make an educated and
satisfying purchase decision. Just as important, they're passionate
about sharing the beauty and wonder of natural colored gemstones
and cultured pearls. |
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Gemtech Int'l. Corp. D/B/A Yosepha Jewelry
Designs
Member
American Gem
Trade Association
Manufactors Jewelers and silversmith Association
Southern Jewelers Association
Ohio Jewelers Association
Jewelers board of Trade |
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