Learn what to look for. Decide
Then make the
choice that's right for you.
Determines the Value of a Colored Gem?
There are three
main factors that determine a colored gemstone's value: color, cut, and natural
brilliance of the gemstone material itself. Not surprisingly, color is the
single most important determinant of value in colored gemstones. Second most
important is the cut of the gemstone, which maximizes the gemstone's life and
brilliance. Generally, the more closely a gemstone approximates its pure
spectral color, the more desirable it is. And the better the cut, the better
the depth of color and liveliness of the gemstone. Clarity and carat weight may
also affect value.
characteristics contribute to the quality and value of colored gems,
intensity of how a gemstone catches light and displays life
the gemstone enhances one's appearance
(closely related to its color)
gemstone's ability, when set in jewelry, to withstand normal wear
available supply (the harder to find, the higher the cost)
desirable a gemstone is in the current market
gems for adornment, symbolism or as a means of exchange
times of turmoil, gems are an investment that can be readily moved
When evaluating a
colored gem, ask yourself the following questions:
Is the shade of
Does the gemstone
have brilliance and life?
Is the color too
dark or too light?
Is the gemstone
uniformly brilliant, or does it have "flat" areas with no life?
Does the gemstone
appeal to me overall?
is affected by a number of variables and primarily by the type and intensity of
the light. A gemstone's color can appear to change under different lights and
environments. A ruby, for example, will not look as red under fluorescent
lighting as it will under ordinary incandescent lights or daylight.
Clearly, color is a
very subjective matter in terms of what is considered attractive and desirable.
Generally, the closer a colored gemstone comes to the pure spectral hue of that
color, the better the color and the more valued the gemstone. The spectral
colors go from pure red to pure violet. White, black, gray and brown are not
spectral colors, but they do affect the tone of a gemstone's color, and,
ultimately, the grading. In general, gemstones that are either very light
(pale) or very dark sell for less per carat. A rich, deep color is desirable,
but not when it approaches black.
used to describe color:
or evenness of color distribution
and richness of color
A good lapidary
(gem cutter) optimizes the proportions of the cut to bring out a gemstone's
maximum intensity and color, making it very desirable. A poor cut significantly
reduces the gemstone's vividness and depth of color.
Some colored gemstones
have what are called windows
where there is no
color. These colorless zones, layers or spots make the
desirable gemstone will have consistent color
stone. Therefore, the evenness and complete saturation of color
will greatly affect
the value of the gem.
cut and proportion affect the depth of color and
projected by the colored gemstone. Unlike diamonds, there is no
cut” for colored gemstones, and colored gemstones are not cut to
proportions. Each stone is different and must be cut based on its
At Shane Co., Tom Shane applies his decades of
and expertise in cutting colored stones to ensure that every
Shane Co. ruby and
sapphire displays maximum brilliance and beauty.
with diamonds, clarity refers to a colored gemstone's purity or absence of
internal inclusions (tiny spots, fractures or anything trapped within the
crystal). While clarity is important, there is less expectation for colored
gemstones to be free of natural markings. Depending on the type of gemstone, an
absence of inclusions in a colored gemstone can be even more rare than in a
diamond and command a higher cost per carat.
The lighter the
gemstone, the more visible the inclusions will be. In a darker gemstone, deeper
color may mask inclusions, making them matter less. A greater concern for
colored gems is the type and placement of inclusions. A large crack (called a
feather) near the surface of a gemstone makes it less durable and disrupts the
play of light, detracting from the value. A small, unobtrusive fracture will
have minimal effect on the gem's durability, beauty and value. Some natural
markings can be desirable to the degree that they validate the origin or
variety of the gemstone.
Size and Density
coral and pearls, all gems are priced by the carat; typically, the greater the
weight, the greater the value per carat (under 50 carats). However, there are a
few colored gemstone varieties that become less valuable per carat if they are
too large to be mounted. Also, weight and size are not the same thing. Some
gemstones weigh more than others because the density (specific gravity) of the
basic mineral is heavier. If a diamond weighs 1.00 carats, the same sized ruby
or sapphire would weigh approximately 1.20 carats.
At Shane Co., our
priority when cutting our colored
gemstones is to
maximize the stone’s brilliance and beauty, not to guard the
weight. We are the only jeweler who does this. The colored
gemstones at other
jewelers are cut to retain as much of the gemstone’s weight
as possible with
little regard to the stone’s beauty.
Some gemstones are
readily available in large sizes. Scarcity of particular sizes among the
different colored gemstones will dictate what is considered "large"
in the market. Like diamonds, colored gemstones of less than one carat sell for
less per carat than gemstones of a full carat or more. Again, what is
considered "large" or "rare" differs by gemstone
actually measures colored gemstones by dimensions in millimeters in addition to
carat weight. Millimeter size of the gemstone often matters more-especially
when matching colored gemstones for a ring, earrings, or other types of