0.60ct Natural Oval-cut Green->Orange color-changing VVS Alexandrite (Sri-Lanka). This gem has never been used/placed/set in a setting.It is utterly undamaged, unmarred and in perfect condition as expected of NWOTags. I have included an Alexandrite article below for your appreciation and enjoyment. Alexandrite is one of the rarest of all colored gemstones available today. More specifically, it is an extremely rare color change variety of chrysoberyl (a cyclosilicate).
Which is an aluminate of beryllium, does not actually belong to the beryl. Mineral group, but rather, it is classified as its own independent mineral group. Phenomenon seen in alexandrite is referred to as the'alexandrite effect'. The change in color can be observed under certain lighting conditions, typically under daylight and incandescent lighting. Alexandrite is also a strongly pleochroic gem.
It can display emerald green, red, orange and yellow colors depending on which angle the stone is viewed from. Properties of alexandrite are completely independent from its unique color change ability. Exhibits an emerald-green color in daylight, and raspberry-red under incandescent lighting. Alexandrite gemstones are typically untreated, but imitation stones do exist.
Type: Natural Alexandrite personally confirmed as Genuine Alexandrite by digital refractometer (RI=1.748), dichroscope (2-color dichroic), polariscope, spectroscope, UV short&long-wave light (no fluorescence), measured Specific Gravity=3.74 -- captej2012. Dimensions: 6.48mm x 4.69mm x 2.18mm. Treatment: Not Heated, Not Treated, Not Enhanced. She came as an infant, moody and maddeningly fickle.
We never knew what would set her towards Green or Orange. Howsoever dynamic though, she is beautiful for it. But now, she bristles and brays with boredom.
She's matured beyond the Elderly Two-of-Us. We understand and will send her to who will love her away. Will you be the next to cherish her ever-changing madness? Stay here, look around and learn. We pride ourselves as good-spirited folks having fun and doing our best to share the joy of Nature's most beautiful and enduring literal treasure -- Natural Gemstones.
Expect to find us cheerful and trustworthy, and we will expect the same of you. About Alexandrite - History and Introduction. Despite its name, chrysoberyl, which is an aluminate of beryllium, does not actually belong to the beryl mineral group, but rather, it is classified as its own independent mineral group.
The history of alexandrite is quite controversial, dating back to the times of Imperial Russia. It is said that the stone was named after the Russian tsar, Alexander II (1818 - 1881), but was discovered by a French mineralist called Nils Gustaf Nordenskiöld (1792 - 1866). When Nordenskiöld first discovered alexandrite in 1834, it was initially thought to be an emerald because it was discovered in emerald mines located in Russia's Ural region, near the Tokovaya River. The specimen was later identified as a chromium bearing, color change variety of chrysoberyl.
Legends claim that the discovery of alexandrite was made on the very day the future tsar of Russia became of age. Inevitably, the red and green color change stone was to be declared the official gemstone of Imperial Russia's Tsardom. The color change phenomenon seen in alexandrite is referred to as the'alexandrite effect'.
Typically, alexandrite exhibits an emerald-green color in daylight, and raspberry-red under incandescent lighting. Alexandrite can also occur with yellowish and pink colors, and extremely rare specimens can exhibit chatoyancy (cat's eye) effects when cut en cabochon. The color change'alexandrite effect' is a result of the strong absorption of light in the yellow and blue portions of the color spectrum.
Most chrysoberyl is colored by iron, but alexandrite color is a result of chromium traces. Through spectroscopic analysis and testing, alexandrite can be distinguished from other similar stones. Ordinary specimens of chrysoberyl may also contain chromium coloring agents, but unless they exhibit a color change ability, they are only identified as chrysoberyl and not alexandrite. Alexandrite Origin and Gemstone Sources.The original source for alexandrite was in the Ural region of Russia, but these mines have long been depleted. For quite some time, the worked out mines of the Urals were thought to have been the only source for large alexandrite stones, specifically specimens weighing 5 carats or more, but very recently in 1987, large specimens were discovered in Minas Gerais, Brazil. Other sources for alexandrite include Myanmar (Burma), Sri Lanka, Tanzania, India (Andhra Pradesh) and Madagascar. Alexandrite's green hue is a result of chromium impurities.
Chromium is the same coloring element found in emerald, the green variety of precious beryl. Sri Lanka (Ceylon) alexandrite is known to exhibit a khaki to brown color change. Alexandrite with Zimbabwe origin usually has very little color change and they are typically darker in color with tints of purple.Tanzanian specimens tend to occur with lighter tones and possess moderate to good color change. Brazilian alexandrite is known to be highly saturated and exhibits a blue to purplish color change. The most desirable alexandrites are those with pure hues and a strong color change ability. Alexandrite stones are typically clean in clarity and once cut and polished, the will exhibit a vitreous luster. Alexandrite in the rough can range from transparent to opaque. Fine alexandrite is considered to be more valuable than blue sapphire, emerald and ruby, especially alexandrite over 1 carat in weight. Sri Lanka is known to produce the cleanest alexandrites, often lacking any visible inclusions at all. Alexandrite is rarely found in large sizes. Any specimens weighing over three carats are considered to be extremely rare. The largest cut alexandrite gemstone weighs 66 carats and is currently located in Washington, D.
Alexandrites are often faceted in traditional shapes such as oval, round, pear, marquise and cushion cuts, but they are also commonly found in fancy shapes such as heart and trillions cuts too. They are not typically cut en cabochon, unless they possess chatoyant properties.
Occasionally, alexandrite stones may be dyed or oiled, but this is not very common. Many alexandrites are synthetic (lab-grown) and others may be natural'simulated' gemstones, such as color change garnet, sapphire or spinel. Many lab-grown (synthetic) alexandrite stones are actually corundum (ruby / sapphire) that has been laced or infused with either chromium or vanadium to provide color. It is very expensive to create synthetic alexandrite, so even lab-grown stones can be very costly. Synthetic alexandrite has been available on the market since the 1960's.The item "0.60ct Natural Oval-cut Green-Orange color-changing VVS Alexandrite (Sri-Lanka)" is in sale since Wednesday, April 17, 2019. This item is in the category "Jewelry & Watches\Loose Diamonds & Gemstones\Loose Gemstones\Alexandrite". The seller is "captej2012" and is located in Canyon Country, California. This item can be shipped worldwide.