The colors of the
rainbow caught forever in glittering jewels that take your breath
away. Colored gemstones can rival diamonds for their beauty but how
are they valued?
sapphires, rubies and emeralds differ in color and weight for
example, there is a consistency in how they are valued. And that
includes lesser known gemstones like tourmaline, alexandrite,
peridots, and garnets as well. The four characteristics that
determine value in a colored gemstones are color, clarity, cut, and
carats, but the most important is color, color, and more color.
The intensity of
the color and the closer it comes to the true spectral color means
the stone has more value. Emeralds should be a pure green, rubies the
reddest red, and sapphires a deep rich blue. As the color varies from
the spectral ideal, the value declines. For example: Burmese rubies
have the best color. Rubies that are a lighter red, reddish orange,
or with a touch of brown or a bit of blue aren't nearly as valuable.
Color is measured
in intensity or saturation, in other words the vividness of the
color. It also reflects the hue, or how close the color approximates
the pure spectral color; tone which is how light or dark ie., how
much black or white is in the color; and finally the distribution of
the color or how even the color is across and within the stone.
The other factors
of clarity, cut, and carats are not as important to the value of a
stone that has the best color and inversely have a greater impact on
the value of a stone that is not as pure a color.
Clarity is the
absence of internal flaws that can be seen with a magnification of
10. Most colored gemstones naturally have inclusions or flaws. A
prime example are emeralds which very rarely don't have flaws. The
lighter the color of the stone the more visible the flaws become,
while the darker the color of the stone the less obvious. The type of
flaw and where it occurs in the stone affects its value as well.
Cut is the way a
stone is faceted to bring out the best characteristics of that
particular stone for its type. The cut brings out the color, fire,
and brilliance of the stone, not sacrificing one for the other.
Unlike diamonds colored gemstones can also be presented as a smooth
rounded surface known as cabochon cut. Cabochon cut sapphires and
rubies often reflect a star and are known as star sapphires and star
Carat is the
weight of the stone, not how big it is. Different types of gemstones
have different weights when cut to the same size. The density of
rubies is greater than the density of emeralds so a one carat ruby
will be smaller than a one carat identically cut emerald. Stones can
be cut to look bigger as well. Some gemstones are more readily
available in larger weights such as amethysts or tourmalines, that
say emeralds. For example: An 18 carat tourmaline will have a lesser
value per carat than a 5 carat alexandrite because large tourmaline
stones are more common than large alexandrite stones.
The best safety
precaution when buying gemstones or gemstone jewelry when shopping
online, is to buy from a reputable jeweler. You will get what you pay for.