Learn About Alexandrite

Alexandrite is an extremely rare color-changing variation of the mineral chrysoberyl that is sometimes referred to as "emerald by day, ruby by night" by gem connoisseurs.
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Alexandrite is an extremely rare color-changing variation of the mineral chrysoberyl that is sometimes referred to as "emerald by day, ruby by night" by gem connoisseurs. It was discovered in the Ural Mountains of Russia in the 1830s and is today found in Sri Lanka, East Africa, and Brazil, but fine material is extremely uncommon and precious.



Alexandrite, a rare form of the mineral chrysoberyl known for its chameleon-like properties, is a rare variety of the mineral chrysoberyl. While it appears green in natural or fluorescent light, it turns brownish or purplish red when exposed to incandescent light from a lamp or candle flame, depending on the source of illumination. As a result of the intricate manner in which the mineral absorbs light, this occurs.

Alexandrite's spectacular color change is commonly referred to as "emerald by day, ruby by night" because of its stunning color change. Several other gemstones similarly change color in response to a change in light source, but the alteration of this gem is so dramatic that it has earned the name "the alexandrite effect" for the phenomena itself.

Aside from that, Alexandrite is a very pleochroic gem, which means that it can appear to be different colors depending on how it is viewed from different angles. Its three pleochroic colors are often green, orange, and purple-red in appearance. In this case, however, it is not the gem's pleochroism that causes the dramatic color change, but the mineral's peculiar light-absorbing capabilities that are responsible for it.

Alexandrite is a relatively costly member of the chrysoberyl family due to its scarcity, particularly in bigger sizes, and because it is a rather rare gemstone. It shares the honor of being the birthstone for June with the cultured pearl and the moonstone.


The Ural Mountains of Russia were the site of the first discovery of abundant alexandrite deposits, which occurred around 1830. Those earliest alexandrites were of exceptionally high quality, with vibrant colors and dramatic color changes. The diamond was given this name in honor of Alexander II, the youthful heir presumptive to the throne. Due to its red and green colors, it drew the attention of the people because they were the same as the imperial Russian national military colors.

The remarkable Ural Mountain deposits did not last indefinitely, and today the majority of alexandrite originates from Sri Lanka, East Africa, and Brazil, rather than the Ural Mountains. The newer deposits contain some fine-quality stones, but many of them exhibit less-detailed color shift and muddier colors than the Russian alexandrites discovered in the nineteenth century. Estate jewelry set with some famous Ural Mountain Alexandrites can still be found on the market. They have maintained their position as the gold standard for this extraordinary gemstone.


Alexandrite, along with pearl and moonstone, is the birthstone for the month of June. Alexandrite is also the gemstone of choice for couples celebrating their 55th wedding anniversary.

Alexandrite Quality Factors


While fine alexandrite appears green to bluish green in natural light, it appears red to purplish red when illuminated by incandescent light. The color saturation ranges from fairly strong to extremely strong. Fine-quality gems have a good level of color intensity, while stones that are too light do not achieve such level of intensity. Stones that are too dark lose their brightness and seem practically black in appearance.

Due to the fact that Russian mines are producing at a relatively low level now, the intense, fine-colored diamonds that were created in large quantities less than 200 years ago are becoming increasingly difficult to find.

Despite the fact that Sri Lankan alexandrites are often larger than their Russian counterparts, their hues are less appealing. The greens of Sri Lankan alexandrite are typically brownish red rather than purplish red, in contrast to the blue-green of Russian stones, and the reds are typically brownish red rather than purplish red.

Alexandrites from Brazil have been discovered in colors that are comparable to those found in Russian material, but the country's production has dropped.

At the moment, alexandrite supply is limited, and fine-color material is particularly difficult to come by.



Clarity  The importance of clean material with good color change and powerful hues has increased dramatically in recent years.

A phenomenon known as chatoyancy, sometimes known as the cat's-eye effect, can be produced when certain types of long, thin inclusions are oriented parallel to each other, resulting in a significant increase in the value of an alexandrite.


When it comes to cut Alexandrites, the most typical design is what is referred to as a mixed cut, which features both brilliant and step-cut pavilions. Brilliant cuts have kite-shaped and triangular facets, while step cuts have concentric rows of parallel facets.

Alexandrite's pleochroism makes it a difficult material to work with for cutters. When cutting alexandrite, the gem is oriented in such a way that the color change is the most pronounced via the crown. It is critical to position the rough in such a way that the fashioned stone displays both the purple red and green pleochroic colors when viewed from the top.


Carat Weight

Alexandrites used in fashion are often small, weighing less than one carat. The cost of larger sizes and higher-quality materials increases substantially.


Mineral: Chrysoberyl

Chemistry: BeAl2O4

Color: Bluish green in daylight, purplish red in incandescent light

Refractive Index: 1.746 to 1.755

Birefringence: 0.008 to 0.010

Specific Gravity: 3.73

Mohs Hardness: 8.5


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