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Lab Alexandrite 15x6.5mm. Marquise Shape "AAA" Color Calibrated Gems
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| ITEM#4825-29529
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| | PRODUCT DETAILS |
| Stone/Shape: | -- | | Stone/Color: | -- | | Cut: | Regular | | Size: | 15x6.5mm. Approx | | Weight (pcs.): | 3.50 carat. Approx | | Origin: | Man Made | | Color: | AAA | | Clarity: | EC (Eye Clean) | | Treatment: | Lab Grown | | Overall Grade: | "AA" |
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Lab Alexandrite 15x6.5mm. Marquise Shape "AAA" Color Calibrated Gems 20 % off Price $5.51 PER piece.
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Lab Alexandrite 14x11mm. Oval Shape "AAA" Color Calibrated Gems
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| ITEM#4825-29503
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| | PRODUCT DETAILS |
| Stone/Shape: | -- | | Stone/Color: | -- | | Cut: | Regular | | Size: | 14x11mm. Approx | | Weight (pcs.): | 8.25 carat. Approx | | Origin: | Man Made | | Color: | AAA | | Clarity: | EC (Eye Clean) | | Treatment: | Lab Grown | | Overall Grade: | "AA" |
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Lab Alexandrite 14x11mm. Oval Shape "AAA" Color Calibrated Gems 20 % off Price $12.99 PER piece.
Lab Alexandrite 15 to 18.5mm. Concave Cut Round Shape "AA" Grade -- Matched Bead Set
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| ITEM#4825-30414
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| | PRODUCT DETAILS |
| Stone/Shape: | -- | | Stone/Color: | -- | | Bead Cut: | Concave Cut | | Size: | 15 to 18.5mm. Approx | | Weight (pcs.): | 63.35 carat. Approx | | Origin: | Man Made | | Color: | AAA | | Clarity: | EC (Eye Clean) | | Treatment: | Lab Grown | | Overall Grade: | "AA" |
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Lab Alexandrite 15 to 18.5mm. Concave Cut Round Shape "AA" Grade -- Matched Bead Set Price $116.40 PER set.
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Lab Alexandrite 13.5mm. Round Shape "AAA" Color Calibrated Gems
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| ITEM#4825-29514
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| | PRODUCT DETAILS |
| Stone/Shape: | -- | | Stone/Color: | -- | | Cut: | Regular | | Size: | 13.5mm. Approx | | Weight (pcs.): | 10.90 carat. Approx | | Origin: | Man Made | | Color: | AAA | | Clarity: | EC (Eye Clean) | | Treatment: | Lab Grown | | Overall Grade: | "AA" |
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Lab Alexandrite 13.5mm. Round Shape "AAA" Color Calibrated Gems 20 % off Price $17.17 PER piece.
[Buy Alexandrite Gemstones]
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- [Buy Alexandrite Jewelry]
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Alexandrite Cabochons]
This rare gemstone is named after the Russian tsar Alexander II (1818-1881), the
very first crystals having been discovered in April 1834 in the emerald mines
near the Tokovaya River in the Urals. The discovery was made on the day the
future tsar came of age. Although alexandrite is a relatively young gemstone, it
certainly has a noble history. Since it shows both red and green, the principal
colours of old Imperial Russia, it inevitably became the national stone of
tsarist Russia.
Beautiful alexandrite in top quality, however, is very rare indeed and hardly
ever used in modern jewellery. In antique Russian jewellery you may come across
it with a little luck, since Russian master jewellers loved this stone.
Tiffany’s master gemmologist George Frederick Kunz (1856-1932) was also
fascinated by alexandrite, and the jeweller’s firm produced some beautiful
series of rings and platinum ensembles at the end of the 19th and beginning of
the 20th century. Smaller alexandrites were occasionally also used in Victorian
jewellery from England.
The most sensational feature about this stone, however, is its surprising
ability to change its colour. Green or bluish-green in daylight, alexandrite
turns a soft shade of red, purplish-red or raspberry red in incandescent light.
This unique optical characteristic makes it one of the most valuable gemstones
of all, especially in fine qualities.
Alexandrite is very scarce: this is due to its chemical composition. It is
basically a chrysoberyl, a mineral consisting of colourless or yellow
transparent chrysoberyl, chrysoberyl cat’s eye and colour-changing alexandrite
(also in cat’s eye varieties). It differs from other chrysoberyls in that it not
only contains iron and titanium, but also chromium as a major impurity. And it
is this very element which accounts for the spectacular colour change. Rarely,
vanadium may also play a part. According to CIBJO nomenclature, only
chrysoberyls displaying a distinct change of colour may be termed alexandrite.
Like many other gemstones, alexandrite emerged millions of years ago in a
metamorphic environment. But unlike many others, its formation required specific
geological conditions. The chemical elements beryllium (a major constituent in
chrysoberyl) and chromium (the colouring agent in alexandrite) have contrasting
chemical characteristics and do not as a rule occur together, usually being
found in contrasting rock types. Not only has Nature brought these contrasting
rock types into contact with each other, but a lack of the chemical element
silica (the second most common element in the Earth's crust) is also required to
prevent the growth of emerald. This geological scenario has occurred only rarely
in the Earth's history and, as a result, alexandrite crystals are very scarce
indeed.
Russia has remained the primary source of alexandrite since gems from the mines
of the Urals became available on the market. When the Russian deposits were
thought to have been exhausted, interest in the unique colour miracle decreased
- especially since alexandrites from other mines hardly ever displayed the
coveted colour change. But the situation changed dramatically in 1987, when
alexandrites were discovered in a place called Hematita in Minas Gerais, Brazil.
The Brazilian alexandrites showed both a distinctive colour change and good
clarity and colour. Thus the somewhat dulled image of the miraculous stone
received another boost. The colour of the Brazilian stones is admittedly not as
strong a green as that of Russian alexandrite, but the colour change is clearly
discernible. Today Hematita is one of the most important deposits of alexandrite
in economic terms. Occasionally alexandrite with chatoyancy is discovered there,
an effect which has not yet been observed in Russian alexandrite. Alexandrites
are also obtained from sources in Sri Lanka, but the hue of these stones
compares less than favourably with that of the Uralian alexandrites. They appear
green in daylight and a brownish red in artificial light. The Tunduru area in
southern Tanzania has also produced some outstanding specimens since the
mid-1990s. Alexandrites are also found in India, Burma, Madagascar and Zimbabwe.
Although this stone is still considered a rarity, specialised gemstone dealers
do stock it, especially since improved trade relationships between Russia and
the rest of the world have ensured a better supply of Russian alexandrites to
the market.
With its good Hardness of 8.5, alexandrite is an uncomplicated stone to wear.
The more distinct the change of colour, the more valuable the stone. A fine
alexandrite should show a vivid bluish-green in daylight and a purplish-red in
artificial light, without any trace of undesirable brown or grey. If the origin
of the stone is known beyond dispute to be Russia, we are talking about a real
rarity of enormous value. Finely faceted alexandrites above one carat are thus
among the most expensive gemstones in the world, rarer than fine ruby, sapphire
or emerald.
Alexandrite is a stone for experts, enthusiasts and connoisseurs, a true
understatement stone. Its uniqueness and high value are not evident at first
sight. The mysterious colour change will only occur on exposure to different
light sources. But if you really get involved in alexandrite, you will be
utterly fascinated by this gem. Maybe you will also feel some of the mysterious
magic and lore ascribed to it. It is considered a stone of very good omen. In
critical situations it is supposed to strengthen the wearer’s intuition, and
thus help him or her find new ways forward in situations where logic will not
provide an answer. Alexandrite is also reputed to aid creativity and inspire the
imagination.
Color: color change, from bluish green (daylight) to purple, red or brown
(incandescent light)
Hardness: 8
Refractive index: 1.74 – 1.77
Density: 3.68 – 3.80
Chemical composition: BeAl2O4
Crystal structure: orthorhombic
Luster: vitreous
Origins: Russia, Brazil, Tanzania, Madagascar, Zambia, Sri Lanka, Burma,
India.
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Alexandrite Cabochons]
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