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Alexandrite changes color from green in daylight to red in
incandescent light. The first time you see it, it is hard to believe your eyes!
Alexandrite was first discovered in
Czarist Russia, in
the Ural mountains, in 1830.
The name “Alexandrite” was coined by mineralogist
Nordenskjöld.
Since the old Russian imperial colors were red and green
it was named after Czar Alexander II on the occasion of his coming of age.
Genuine Alexandrite is one of the world's rarest and most coveted Gemstones,
it's so rare that most people have never even seen a genuine Top Quality
Alexandrite, so feel free to browse through our
inventory.
Alexandrite is in
the Chrysoberyl mineral family and is one of the
most fascinating gemstones throughout history. Alexandrite
is the variety of Chrysoberyl that displays a change-of-color from green to red.
A distinct color change is the primary qualification for a Chrysoberyl to be
considered alexandrite. Although alexandrite is strongly trichroic, its color
change has nothing to do with pleochroism. Instead, like all other color-change
gems, it results in a near-equal transmission of the blue-green and red portions
of the spectrum, coupled with strong absorption in the yellow. Thus its color is
dependant on the spectral strength of the light source. Incandescent light is
strongly tilted to the red end, thus causing alexandrite to appear reddish.
Daylight, is more equally balanced. Since our eyes are most sensitive to green
light, the balance is tipped to the green side. The strength of the color change
is related to the difference in the areas of transmission, relative to the
absorption in the yellow. The greater the difference, the stronger the color
change.
The color is actually caused by Chromium.
A color change occurs in very few
gemstones. For alexandrite, the quality of
the color change is paramount. While the holy grail is a gem whose color changes
like a traffic light from green to red, such a stone has yet to be found. In
fine examples, the change is typically one from a slightly bluish green to a
purplish red. The quality of color change is often referred to by dealers in a
percentage basis, with 100% change being the ideal. Stones that display a change
of 30% or less are of marginal interest and are arguably not even alexandrite.
Significant brown or gray components in either of the twin colors will lower
value dramatically.
The natural color change
in Alexandrite ranges from various shades of Green (blue-greens, kelly-greens,
olive-greens, teal-greens, etc.) when the gem is under "fluorescent"
lighting, or in natural outdoor light "in the shade" (not direct sunlight)...
then the color changes to various shades of Red (burgundy-reds, purplish-reds,
reddish-purples, violetish-purples, amethyst, etc.) when exposed to light
in a room with only incandescent light, tungsten light, or candlelight
(a flashlight will bring out the color change too). To get the maximum
color change effect the gem is best viewed in a dark room with no outdoor
light at all, then turn on a fluorescent light to see the green shade,
then turn on a standard incandescent light bulb with the fluorescent light
off to see the reddish shade. You can cycle the lights back and forth
to see the distinct color change. Alexandrite will normally darken when
taken out into direct sunlight, since it is subjected all the colors in
the spectrum, also if subjected to several types of lighting sources
at the same time the colors may twinkle with both the red and the
green color bouncing around different facets in the stone. When the
primary color has a bit of brownish in with the green, this is due to the
bleeding of the two colors. Typically this is referred to as the
percentage of color change. The higher the color change percentage, the
more expensive the gem.
When the color change from fluorescent light to tungsten light is not
an obvious color change from one of the various shades of green to one
of the shades of red, the gem is usually called "alexandrite like" or a
"color change Chrysoberyl" since it does not quite have the distinct greenish
to reddish color change to be called "Alexandrite".
In terms of clarity, alexandrite is comparable to ruby,
with clean faceted stones in sizes of one carat being rare and sizes over a
carat and especially above 2–3 carats are extremely rare. Negative crystals and
parallel rutile silk are common inclusions. Clarity, however, is a minor issue, as long as the
inclusions do not affect the stone's durability. The color change is what
represents the majority of the gem's value. Color, brilliance, and cut (in that
order) are the 3 things that primarily affect the gem's final price. The more
vivid the colors of a color change, the more valuable the gemstone. Ideally, you
want a dramatic color change with a medium to medium-dark tone and intense
color.
In the market, Alexandrite is found in a variety of
shapes and cutting styles. Ovals are cushions are the most common, but rounds
are also seen occasionally, as are a few other shapes.
Alexandrite can be found in jewels of the period as it was
well loved by the Russian master jewelers. Master gemologist George Kunz of
Tiffany was a fan of alexandrite and the company produced many rings featuring
fine alexandrite in the late nineteenth and early twentieth century, including
some set in platinum from the twenties. Some Victorian jewelry from England
features sets of small Alexandrite stones. The
original locality for alexandrite is Russia.
Russian Alexandrite is extremely
rare, the original source in Russia's Ural Mountains has long since dried up
after producing for only a few decades. A few Russian miners are still
working those trailings there in the Urals, and they are finding a few fine
gems, but only in very limited quantities. We secure rare Russian gems from the
Cheremsha and Malyshevskaya mines in the Ekaterinburg area of the
Ural mountains as soon as they are found and made available to us. Some are small stones, less than a carat, but they all have a dramatic color change.
Color change gemstones of Russian origin like this is particularly rare and
highly valued by collectors. In 1987, an important new deposit was discovered at
the Hematita mine in Nova Era, Brazil. Until this find,
Brazil was only known for it's inexpensive gems. The old Hematita mine is
still in production, but the new owners are finding it necessary to dig deeper
into the mountain. We have access to the finest Alexandrite from these mines.
At the present time there are only limited amounts of these goods on the market,
and no one knows how much more the mine can produce, but the material presently
is of very high quality. This Brazilian Alexandrite shows a striking similarity to the fine Russian gems, having an attractive color change from bluish-green to raspberry like purplish-red. These Brazilian
mines
have also virtually dried up after producing for only a
few years, so they too are also in
very limited quantities. These also remain extremely rare and expensive. Since
we have have direct access to many of the original stones taken out
of the mines we can offer them to you, a few of which are larger stones over a carat. We have
also secured some of the finest
Alexandrite from Sri Lanka. Many of these fine gems are from the
Rakwana area, and they are absolutely stunning, changing from a vibrant
bluish-green to a very nice reddish-Purple. We also usually have a few fine specimens
from the Ratnapura region. These fine gems have a very good color change also,
but it's usually a little more of an olive green changing to a purple stone. Not quite as dramatic as the
Russian, Brazilian, and Rakwana material,
but very nice indeed. The lower price per carat makes this choice a little more obtainable. The
availability this fine material on our website means a new generation has the
opportunity to own this beautiful and rare gemstone. Alexandrite
stones have also been found in Zimbabwe, Burma, Tanzania, Madagascar, and India,
but we don't feature these since we are very selective and only want to bring
you the best of the best.
When evaluating alexandrite, pay the most attention to the color change: the
more dramatic and complete the shift from red to green, without the bleeding
through of brown from one color to the next, the more rare and valuable the
stone. The other important value factors are the attractiveness of the two
colors - the more intense each color is the better - then look for the clarity,
and then the cutting quality.
Alexandrite is one of the world‘s most expensive gems,
with prices similar to those fetched by fine ruby or emerald. But like all gem
materials, low-quality (i.e., non-gem quality) pieces may be available for a few
dollars per carat. Such stones are generally not clean enough to facet. Because of the rarity of this gemstone,
large sizes command very high premiums.
Facet-quality alexandrite rough is extremely rare. Thus
even the very small stones less than 0.5 ct. (melee) can sell for thousands of
dollars per carat. Any fine faceted alexandrite around one and a half carats or
especially above two carats should be considered quite large. Stones of quality
above five carats are extremely rare.
We do not
sell Synthetics. To assure you that you are getting a genuine Alexandrite
from us, we normally provide you with a Gem Identification Report from
a reputable Independent Gem Laboratory. The cost of this Gem Report
is included in the price of the gem. Some of the smaller Alexandrite
gems may not have a Gem Report listed, in that case we will normally provide
a "Statement of Sale and Evaluation for Insurance", and this report would
include the specific details on that particular gem as our guarantee of
authenticity.
Alexandrite is an excellent investment stone since it is definitely
considered a "Very Rare"
gem.
TREATMENTS - Typically Alexandrite is
not treated since it would adversely affect the natural color change phenomena.
CARE - Alexandrite is also excellent in
jewelry since it is quite hard, however, as with all Chrysoberyl, it should
not
be cleaned in an ultrasonic or steam cleaner. We recommend
Ionic
Cleaners and/or warm, soapy water and a soft brush as the best way to clean
Alexandrite in jewelry.
NOTE:
While true synthetic alexandrite does exist, the vast
majority are actually a synthetic color-change sapphire, colored
by vanadium, not synthetic alexandrite. Since synthetic color-change sapphires
have been made from about 1909 onwards, it is entirely possible to have a piece
that could be classified as an antique. Indeed, many a traveler has returned
from a third-world trip with what they think is natural alexandrite, only to
later discover (or have their heirs discover) that what they have is a cheap
synthetic sapphire worth but a few dollars per carat.
If you own a gem that you suspect is an alexandrite, and you are wondering how
to tell the difference between synthetic and genuine alexandrite, we recommend
you send the stone to a reputable Gem Laboratory and ask for a Gem
Identification Report. Please don't call and ask me, I can't tell you anything
over the phone except that you need to send the stone to a reputable Gem Lab,
and typically a local Jeweler can't do this.
The following links are to reputable Gem Laboratories
and Appraisers (in Alphabetical
order).
Prices for gem reports may range from $100 to $1,000, depending
on how much detail you want on the report.
AGL
| AGTA
| GIA
| GRS
| GUBELIN
| GUILD
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