Many
attractive Emeralds and Emerald Jewelry are purchased without
any consideration as to their investment qualities. They simply
appeal to the buyer, or the shopper wants an in-expensive keepsake
as a reminder of a romantic/fun time in Cartagena.
But, for those considering
purchasing Emeralds of investment quality, here are some important
factors. The most important determiner of the price of an Emerald
is its color. Following this, the stone's clarity, carat weight, and
the amount and type of inclusions are the other major determinants
of value. Dark, clear stones with few or no visible inclusions command
prices higher than those of equally fine diamonds.
As Type III gems, Emeralds are the only major gemstones expected to
have visible inclusions, known as "gardens." Although gaseous,
mineral, or fracture inclusions can structurally weaken an Emerald,
the green gem is rated 7.5-8 on the Mohs hardness scale and are, therefore,
"harder than most steel." Diamonds have an Mohs hardness
of 10.
Colombian goldsmiths use
only 18kt gold (or purer) when working with Emeralds, and take special
care to protect the gems from heat while setting them. Bezelled settings
are recommended, as they provide all-around protection to the stone.
Bezelling also allows jewelers to place quality stones of slightly
less color in a setting which darkens the stone's hue while amplifying
its green fire. Finally, most Colombian Emeralds are "oiled,"
a process by which palm oil, or a similar oil, is applied under pressure
(about 700 pounds per square inch) to fill the minute inclusion voids
in the gems, thereby optimizing the aesthetic beauty of the stone.