you gaze deep inside a crystal ball, you will see a versatile
gemstone, one of the most popular gems on earth. Beautiful quartz,
the "rock crystal" used in ancient times to make crystal balls and
bowls, is today more often seen set in gold jewelry. Despite the
popularity of quartz gems like amethyst, citrine, ametrine,
rose quartz, onyx, agates, chrysoprase, rutilated quartz, and
other quartz gemstone varieties, many people in the jewelry
industry take quartz for granted because of its affordable price.
Throughout history, quartz has been the common chameleon of
gemstones, standing in for more expensive gemstones ranging from
diamond to jade. But the incredible variety of quartz is now
beginning to be appreciated for its own sake.
Purple to violet amethyst and yellow to orange citrine are jewelry
staples that continue to increase in popularity. Ametrine combines
the appeal of both amethyst and citrine as well as both the purple
and yellow in one bicolored gemstone. Different colors and types
of chalcedony, from agate to chrysoprase, have grown in popularity
with the growing appreciation for carved gemstones and art cutting
and carving. And unusual quartz specialties like drusy quartz,
with its surface covered by tiny sparking crystals, and rutilated
quartz, which has a landscape of shining gold needles inside, are
adding variety and nature's artistry to unusual one-of-a-kind
Rose quartz The pale pink color of quartz, which can range
from transparent to translucent, is known as rose quartz. The
color is a very pale and delicate powder pink. Transparent rose
quartz is very rare and is usually so pale that it does not show
very much color except in large sizes. The translucent quality of
rose quartz is much more available and is used for beads,
cabochons, carvings, and architectural purposes.
Smoky quartz Smoky quartz is a brown transparent quartz
that is sometimes used for unusual faceted cuts. The commercial
market is limited due to the limited demand for brown gemstones.
This variety was sometimes known as smoky topaz in the past, which
is incorrect and misleading, since the mineral variety is quartz,
Tiger's Eye quartz contains brown iron which produces its
golden-yellow color. Cabochon cut stones of this variety show the
chatoyancy (small ray of light on the surface) that resembles the
feline eye of a tiger. The most important deposit is in South
Africa, though Tiger's eye is also found in Western Australia,
Burma (Myanmar), India and the U.S. (California).
Rock crystal The transparent colorless variety of quartz is
still known as rock crystal. Long ago, people believed that rock
crystal was a compact form of ice: crystallos actually means
"frozen." The best rock crystal has the clarity and shimmer of
water. Although colorless quartz is relatively common, large
flawless specimens are not, which is why crystal balls these days
are made of glass, not quartz. Rock crystal has often been used in
jewelry, particularly carved pieces. Many stunning Art Deco
jewelry designs featured the black and white quartz combination of
rock crystal and onyx. Colorless quartz crystals have also become
popular in jewelry due to the popularity of legends about the
powers of quartz crystals. Many people believe that wearing quartz
crystals benefits a person's health and spiritual well being.
Rutilated quartz and tourmalinated quartz While most
varieties of transparent quartz are valued most when they lack
inclusions, some varieties are valued chiefly because of
inclusions! The most popular of these is known as rutilated
quartz. Rutilated quartz is transparent rock crystal with golden
needles of rutile arrayed in patterns inside. Every pattern is
different and some are breathtakingly beautiful. The inclusions
are sometimes called Venus hair. Less well known is a variety
called tourmalinated quartz which, instead of golden rutile, has
black or dark green tourmaline crystals.
Quartz that is formed not of one single crystal but finely grained
microcrystals is known as chalcedony. The variety of chalcedony is
even greater than transparent quartz varieties because it includes
cryptocrystalline quartz with patterns as well as a wide range of
solid colors. Agates are banded, bloodstone has red spots on a
green ground, moss agate has a vegetal pattern. Jasper sometimes
looks like a landscape painting. Another staple of the jewelry
industry is black onyx, chalcedony quartz which owes its even
black color to an ancient dyeing process that is still used today.
Carnelian, another chalcedony valued in the ancient world, has a
vivid brownish orange color and clear translucency that makes it
popular for signet rings and seals. Chrysoprase, a bright apple
green translucent chalcedony, is the most valued. It was a
particular favorite of Frederick The Great of Prussia, who loved
its bright green color. It can be seen today decorating many
buildings in beautiful Prague, including the Chapel of St Wencelas.
Chrysoprase is found today mostly in Australia. Unlike most other
green stones, which owe their color to chromium or vanadium,
chrysoprase derives its color from nickel. Its bright even color
and texture lends itself well to beads, cabochons, and carvings.