The pearl was the favored gem of the wealthy during the time of the
Roman Empire. This intriguing gift from the sea had been brought back
from the Orient by the Crusaders. Roman women wore pearls to bed so
they could be reminded of their wealth immediately upon awakening.
Pearls were once considered an exclusive privilege for royalty. A law
of 1612 drawn up by the Duke of Saxony prohibited the wearing of
pearls by nobility, professors, doctors or their wives.
An old Arab legend tells us that pearls were formed when dew drops
filled with moonlight fell into the ocean and were swallowed by
oysters. The modern scientific explanation is not nearly as romantic
but still quite fascinating.
A natural pearl (often called an Oriental pearl) forms when an
irritant works its way into a particular species of oyster, mussel or
clam. As a defense mechanism, the mollusk secretes a fluid to coat
the irritant. Layer upon layer of this coating is deposited on the
irritant until a lustrous pearl is formed. A cultured pearl undergoes
the same process. The only difference is that the irritant is a
surgically-implanted mother-of-pearl bead or piece of shell. The core
is, therefore, much larger than in a natural pearl. As long as there
are enough layers of nacre to result in a beautiful, gem-quality
pearl, the size of the nucleus is of no importance to beauty or durability.
Imitation pearls are a different story altogether. In most cases, a
glass bead is dipped into a solution made from fish scales. This
coating is thin and may eventually wear off. The island of Mallorca
is known for its imitation pearl industry.
On the other side of the world, pearls were being worn for adornment
by the American Indians. The freshwater pearls of the Mississippi
River were strung into necklaces, sewn onto headdresses and set into
copper ornaments. Freshwater pearls occur naturally and are generally
very irregular in shape, with a puffed rice appearance being the most
common. San Angelo, Texas in the late 1800's was known as the
Freshwater Pearl Capital of the US. Even today the numerous lakes in
this region yield fine freshwater Pearls.
Fine natural pearls are quite rare. The Persian Gulf has always been
the source of the finest natural saltwater pearls. Other sources are
the waters around Sri Lanka, Australia, Japan, Mexico, Panama,
Venezuela and the Micronesian Islands.
One of the largest saltwater pearls still in existence is the Hope
Pearl, first acquired by Henry Philip Hope in the 19th century. It is
two inches long, and varies between 31/4 and 41/2 inches in
circumference. It is on display at the British Museum of Natural
History. Most saltwater Pearls now come from Tahiti and are known as
South Sea Pearls. The nuclei begins larger (at least 8 mm) yield
natural Pearls in the 10-15 mm size.
Japan and China are major source of cultured freshwater pearls. The
smaller nuclei and growth periods less than 8 years yield smaller
Pearls in the 2.5 to 8 mm range. Above that the retail prices soar to
several hundred dollars for 8.5, 9.0 or 10.0 mm fine White Pearls.
Mohs hardness: 2.5 to 4.5
Alexandrite
One of the most interesting, yet least known, of the important
gemstones, Chrysoberyl deserves a special recognition for its rarity
and astounding beauty. The rare presence of chrome traces turns
Chrysoberyl into Alexandrite. The stone was named after Czar
Alexander II of Russia. Alexandrite changes color from soft green in
sunlight to deep red in candle or artificial light. The composition
is the same as Beryl, but the distinct pleochroism shows deep red,
orange-yellow and green colors. Because of the chromium in
Alexandrite it may fluoresce a dull red in short-wave and long wave UV.
SOURCES:
Russia:
Has long been the most desirable source for gem Alexandrite. The
finest comes from the Takowaja emerald mines in the Ural mountains.
This is where it was discovered in 1830.
Brazil:
Alexandrite from Brazil is mined in the States of Minas Gerais and
Bahia. Until the discovery of its new Alexandrite vein, Brazil
commanded little or no respect as an Alexandrite producer. At present
all major Brazilian mines are under government control. Recent finds
have led to a great deal of infighting between mine owners. The
"wars" became so violent that the government trenched a
moat around and posted soldiers upon, the only remaining operating
mine. For prized stones, the trade counts on Sri Lanka, but only on a
sporadic basis. These stones always seem to have an undertone of
brown or yellow. Seldom do you see the fine 100% color change
exhibited in the new Brazil or old Russian material. Sri Lankan
material can often exceed 20 cts in size and be extremely clean. But
the faint orange color change usually can only be seen in laboratory
conditions. Nobody knows how much material from the new Brazilian
find has been cut. But insiders estimates range from 5,000 to 10,000
carats. These stones boast admirable color purity and richness. The
completeness of the color change in most of the material is one of
the most amazing things about the new find.
Nigeria:
This new source of Alexandrite is yielding beautiful Blue Green
material with much better clarity than the Brazilian material.
However, the color change is more to an orangish pink color rather
than rose or red.
CLARITY:
Alexandrite is a TYPE III gemstone as classified by the Gem Institute
of America. That means you can expect Alexandrite to have numerous
and eye visible inclusions. The stone pictured about would be
considered very clean even though you can easily see the inclusions
with your naked eye.
PRICE & SIZE:
As of May 2005, fine quality, nearly eye clean, 2-to-3 carat
Brazilian stones were already commanding prices of $20,000 to $35,000
per carat. Although 30 to 40 carat Russian Alexandrites are known to
exist, most are around 8 carat and you rarely see Siberian stones
that have the right color and purity. These stones can fetch upwards
of $50,000 per carat. One should not forget that the primary buyers
of Alexandrite for some time now have been the Japanese. Especially
fond of sizes between 2 and 4 carats, they have so far swallowed
prices exceeding $25,000 per carat. Click here for our current price guide.
CUT:
The nature of the Alexandrite crystal and its unique trichoric
phenomenon dictates the rough will be cut for purity, color change,
and size. Stones are not cut to "calibrated" size, nor
seldom is the rough wasted to cut stones over 5 mm round. Pearshape,
princess, trillions, emerald-cut, or marquette shapes likewise are
not the shape of choice to which Alexandrite is fashioned. Rather the
antique or cushion shape, small rounds under 3 mm or elongated ovals
dominate the finished supply.
How to Care for Alexandrite:
Alexandrite is rated “excellent” for everyday wear however
one must still use caution and protect it from harsh chemicals,
extreme temperatures and scratches. The best way to clean the stone
is with mild dish soap and warm water, using a soft toothbrush.
