By: Diane Nicole Go, GIA Graduate Gemologist
Did you know that there are gemstones that can actually change color? Take Alexandrite for example.
Known as an “Emerald by day, Ruby by night”, an Alexandrite is as rare as it is beautiful because it can appear in different colors— depending on the kind of light you view it in. Under daylight or fluorescent light, an Alexandrite shows a lovely green color, which then changes to a brownish or purplish red under incandescent, yellow light. While some variants of Garnet and Sapphire show color-change as well, Alexandrite is the more well-known color changing gem. That’s why the phenomenon is often dubbed as “the Alexandrite effect”.
Along with Pearl and Moonstone, Alexandrite is the birthstone for June babies. It’s also the gemstone signifying a couple’s 55th wedding anniversary.
Get the lowdown on this exotic gem and find out why its value and rarity can even a Ruby or Diamond.
Unlike other gems that come with a wealth of history, an Alexandrite is a relatively modern stone.
Alexandrite, which was named after Russia’s Prince Alexander II, was first discovered in the year 1830 in Russia’s Ural Mountains. At first, workers thought the green stones that they dug up were Emeralds, but when placed by the light of their campfire, it shone a rich red hue. They were perplexed at first, especially since the gems were green again under daylight.
And because this unique gem showed green and red colors that were similar to the military colors of imperial Russia, it became the country’s national stone.
The Ural Mountains initially yielded an abundant supply of fine-quality Alexandrite gemstones with vivid hues and dramatic color change. However, this didn’t last forever. Nowadays, most Alexandrite comes from Sri Lanka, East Africa and Brazil, and while some are good quality, most of them show less color change and muddier hues compared to the 19th century beauties.
To this day, the benchmark for good quality Alexandrite (which can be found in estate jewelry) are those mined from the Ural Mountains.
Alexandrite is the rare color change variety of the mineral Chrysoberyl. Its rarity can be attributed to its very precise chemical composition— a Beryllium Aluminum Oxide combined with trace elements like iron, titanium and chromium in the right conditions. This unlikely occurrence is what makes the stone so valuable.
When viewed under white light, an Alexandrite is yellowish, brownish, grayish or even bluish green, which then changes to an orangy, brownish red or even purplish red under yellow light. Fine-quality Alexandrite, however, shows a bluish green color, just like grassy Emerald, and a fiery purplish red color like Ruby. The more saturated and stronger the color change, the more expensive the Alexandrite.
If an Alexandrite comes with a very strong color change and a price that is too good to be true, be careful. You might be looking at a synthetic, lab-grown Alexandrite.
Natural Alexandrite can be found in Brazil, Russia, Sri Lanka, Madagascar, India, Myanmar, Zimbabwe and the southern part of Tanzania.
Some Alexandrites can even show another type of special phenomenon: Cat’s Eye. When inclusions on a cabochon-cut gem form a thin line in the center that shifts when you tilt the stone, you have for yourself a Cat’s Eye Alexandrite—another rarer gem.
Alexandrite unlocks the Crown chakra, which connects you to the physical and spiritual side of the world. This helps you find your center, and find balance in what you do.
Alexandrite is a gem with ever-changing colors, which signifies that life is filled with changes and challenges. It serves as a reminder that you should fill your life with happy moments, and to find your purpose instead of dwelling too much on the past.
Much like its two colors, Alexandrite focuses on both the internal and external aspect of a person. On one end, it helps strengthen your intuition and boost your creativity, while also keeping you grounded and stable. It also helps strengthen your willpower, yet at the same time teaches self-disciplined people to rest and take things easy once in a while.
Keeping an Alexandrite with you also helps you get in touch with your emotional side. It allows you to accurately assess other people’s emotions, as well as your own, in order to achieve emotional maturity. Alexandrite is useful for your emotional well-being, as it promotes good self-esteem and the ability to see the good in the world. This is a good stone to have or to give people who are pessimistic, unsure and lost, as it aids in your self-development.
CARE AND CLEANING
Alexandrite has an 8.5 ranking in the Mohs scale of Hardness, making it relatively hard. It can withstand day-to-day wear, as it has excellent toughness. This is why Alexandrite can be fashioned into all kinds of jewelry, even rings. It’s easy to take care of as well because it can withstand heat and light without sustaining any damage.
In order to clean your Alexandrite jewelry, warm, soapy water and a soft-bristled toothbrush is always a safe method. However, it can withstand both ultrasonic and steam cleaners. The only exception is when the Alexandrite is fracture-filled (wherein cracks are filled with resin or glass). Those kinds of gems can only be cleaned with a mild soap and warm water.
CHOOSING THE RIGHT ALEXANDRITE
Color change is the most important factor for an Alexandrite’s value. This factor precedes all others. The more distinct the shift in color, the higher the value.
The basis for fine-quality Alexandrite are those mined from the Ural Mountains. A highly saturated, vivid Alexandrite with an emerald green to bluish color under daylight and a red to purplish red color in incandescent light will definitely fetch a high price in the market. Those that are too light cannot show a strong color change, while a stone that is too dark cannot show the difference in color under different lighting. Plus, the latter will end up looking inky—almost black. Undertones like brown and yellow decrease the value of an Alexandrite.
Currently, fine-quality gems are hard to come by, given that Alexandrite supplies are low.
Alexandrites will never be flawless, but they do come with a few inclusions. The more eye-clean the gem is, plus the better the color change and the more vivid the color of the gem itself, the higher the price. Look for a gem with lesser inclusions and be very careful about those with large cracks or chips that threaten its durability. You should also be careful of gems whose cracks are filled to make it look clean. Those can cause the value to drop.
A cabochon-cut Alexandrite with long, thin needle-like inclusions that form a cat’s eye effect increase an Alexandrite’s value. This is called a Cat’s Eye Alexandrite, and it is rarer than a normal Alexandrite.
An Alexandrite is challenging to cut, as cutters prioritize the shape that will allow its color change to shine through. Oftentimes, Alexandrites are cut in fancy shapes based on the shape of its rough. Most Alexandrites are cut as mixed cuts (brilliant-cut top and step-cut bottom), but the Cat’s Eye Alexandrites are always cut as cabochons to emphasize the eye.
When buying an Alexandrite based on cut, it is important to assess the proportion of the cut. However, you don’t need to be too critical about it having a “perfect shape”, since it is often based on your preference—be it a round or cushion cut, and the like.
Given that an Alexandrites are rare, small sizes that weigh less than a carat are common. Larger sizes with better quality color change and saturated hues will definitely fetch for a high price. Stones above 5 carats are very expensive.
Alexandrite is an exotic gem—a luxury that only few can afford. If you ever come across an Alexandrite with lovely colors, consider yourself lucky. This versatile piece works well for any occasion, can be worn everyday and can even be passed down to future generations.