Buying gemstone jewelry can be fun, exciting and confusing.
Whether you’re considering a gift of gemstone jewelry for
someone special or as a treat for yourself, take some time to
learn the terms used in the industry. Here’s some information to
help you get the best quality gemstone jewelry for your money,
whether you’re shopping in a traditional brick and mortar store
or online.
Gemstones Natural gemstones are found in nature.
Laboratory-created stones, as the name implies, are made in a
laboratory. These stones, which also are referred to as
laboratory-grown, {name of manufacturer} – created, or
synthetic, have essentially the same chemical, physical and
visual properties as natural gemstones. Laboratory-created
stones do not have the rarity of naturally colored stones and
they are less expensive than naturally mined stones. By
contrast, imitation stones look like natural stones in
appearance only, and may be glass, plastic, or less costly
stones. Laboratory-created and imitation stones should be
clearly identified as such.
Gemstones may be measured by weight, size, or both. The basic
unit for weighing gemstones is the carat, which is equal to
one-fifth 91/5th) of a gram. Carats are divided into 100 units,
called points. For example, a half-carat gemstone would weigh
.50 carats or 50 points. When gemstones are measured by
dimensions, the size is expressed in millimeters (for example,
7×5 millimeters).
Gemstone treatments or enhancements refer to the way some gems
are treated to improve their appearance or durability, or even
change their color. Many gemstones are treated in some way. The
effects of some treatments may lessen or change over time and
some treated stones may require special care. Some enhancements
also affect the value of a stone, when measured against a
comparable untreated stone.
Jewelers should tell you whether the gemstone you’re considering
has been treated when: the treatment is not permanent; the
treated stone requires special care; or the treatment
significantly affects the value of the gemstone.
Some common treatments that you may be told about and their
effects include: • Heating can lighten, darken or change the
color of some gems, or improve a gemstone’s clarity. •
Irradiation can add more color to colored diamonds, certain
other gemstones and pearls. • Impregnating some gems with
colorless oils, wax or resins makes a variety of imperfections
less visible and can improve the gemstones’ clarity and
appearance. • Fracture filling hides cracks or fractures in gems
by injecting colorless plastic or glass into the cracks and
improves the gemstones’ appearance and durability. • Diffusion
treatment adds color to the surface of colorless gems; the
center of the stone remains colorless. • Dyeing adds color and
improves color uniformity in some gemstones and pearls. •
Bleaching lightens and whitens some gems, including jade and
pearls.