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Color

Color Description; Occurrence

1 ct.

3 ct.

5 ct.

10 ct.

30 ct.

117 / 212 - color change: medium very strongly bluish Green; slightly greyish / medium strongly purplish Red; very slightly brownish

Alternative name, occurrence category: Very rare

8033,87

12,079.10

16,124.33

No data

No data

099 / 213 - color change: medium very slightly bluish Green; slightly greyish / medium strongly purplish Red; slightly brownish

Alternative name, occurrence category: Very rare

9,311.12

13,999.48

18,687.83

No data

No data

117 / 195 - color change: medium very strongly bluish Green; slightly greyish / medium Purple; slightly greyish

Alternative name, occurrence category: Very rare

7,003.52

10529,95

14,056.37

No data

No data

114 / 150 - color change: medium light very strongly bluish Green; slightly greyish / medium light Blue; slightly greyish

Alternative name, occurrence category: Rare

2,701.70

4,062.06

5,422.42

No data

No data

093 / 021 - color change: light very slightly bluish Green; very slightly greyish / light reddish Orange; very slightly brownish

Alternative name, occurrence category: Rare

1,960.99

2,948.39

3,935.78

No data

No data

065 / 026 - color change: medium light yellowish Green; very slightly greyish / medium reddish Orange; very slightly brownish

Alternative name, occurrence category: Rare

1,452.93

2,184.52

2,916.10

No data

No data

057 / 033 - color change: medium light greenish Yellow; very slightly greyish / medium light Orange; very slightly brownish

Alternative name, occurrence category: Rare

726.47

1,092.26

1,458.05

No data

No data

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Alexandrite

Alexandrite is one of the rarest of all colored gemstones available today. More specifically, it is an extremely rare colour change variety of chrysoberyl (a cyclosilicate). 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, colour 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 colour change stone was to be declared the official gemstone of Imperial Russia's Tsardom.

The colour change phenomenon seen in alexandrite is referred to as the 'alexandrite effect'. The change in colour 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 colorus depending on which angle the stone is viewed from. The pleochroic properties of alexandrite are completely independent from its unique color change ability. Typically, alexandrite exhibits an emerald-green colour in daylight, and raspberry-red under incandescent lighting. Alexandrite can also occur with yellowish and pink colous, and extremely rare specimens can exhibit chatoyancy (cat's eye) effects when cut en cabochon. The colour change 'alexandrite effect' is a result of the strong absorption of light in the yellow and blue portions of the colour spectrum.

Most chrysoberyl is colored by iron, but alexandrite colour 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 colouring agents, but unless they exhibit a color change ability, they are only identified as chrysoberyl and not alexandrite.

Alexandrite Origin and Gemstone Sources Back to Top

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.

Buying Alexandrite and Determining its Gemstone Value

Alexandrite Colour

Alexandrite's green hue is a result of chromium impurities. Chromium is the same colouring element found in emerald, the green variety of precious beryl. Sri Lanka (Ceylon) alexandrite is known to exhibit a khaki to brown colour change. Alexandrite with Zimbabwe origin usually has very little colour change and they are typically darker in colour with tints of purple. Tanzanian specimens tend to occur with lighter tones and possess moderate to good colour change. Brazilian alexandrite is known to be highly saturated and exhibits a blue to purplish colour change. The most desirable alexandrites are those with pure hues and a strong colour change ability.

Alexandrite Clarity and Luster

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 Cut and Shape

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.C.'s Smithsonian Institution. 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.

Alexandrite Treatment

Alexandrite gemstones are typically untreated, but imitation stones do exist. 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 colour 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 colour. 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 1960s.

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Alexandrite, click here for more information

Historical values 2005 - 2016

Current values per colour and carat weight