Alexandrite is one of those gemstones that people often believe must be synthetic, both because of its very unusual properties and a name which sounds like it might have been conceived by scientists. However, the truth is that this rare stone, best known for its ability to change colors from red to green depending on lighting conditions (red in incandescent light, green in sunlight), is completely natural and absolutely beautiful. In fact, the saying “emerald by day, ruby by night” comes pretty close to describing the appearance of true alexandrite.
It’s certainly easy, of course, to buy inexpensive alexandrite rings with lab-created stones. However, the stunning look of a high-quality, real alexandrite ring is truly unique – and it is, unfortunately, priced accordingly.
Here’s a closer look at these rare stones, and the gorgeous pieces of jewelry which are designed around them.
The History of Alexandrite
Alexandrite wasn’t even known to exist until almost the middle of the 19th century; the first specimens were uncovered while miners were digging for emeralds in Russia’s Ural Mountains in April, 1834. Because the discovery came on the same day that the nation’s future Tsar Alexander II came of age (or so the story goes), the stone was named after Alexander. Even more appropriately, the national colors of Tsarist Russia were green and red – the two colors prominently displayed by alexandrite as it changes color – so it’s understandable that the gemstone became the national stone of Imperial Russia.
That country’s jewelers were quite taken with this new and fascinating gemstone and worked with it extensively through the rest of the 19th century, fashioning a spectacular assortment of jewelry utilizing the stone. Vintage alexandrite rings from Russia are among the hardest to find, and most expensive, pieces of antique jewelry in the world. Later in the century, alexandrite was a favorite of Tiffany master gemologist George Frederick Kunz, leading to the creation of a number of stunning alexandrite-and-platinum Tiffany pieces from the late 19th century through the early years of the 20th century. Other jewelers worked with the stone as well, but because of the rarity and cost of top-quality alexandrite, not many rings were made and relatively few have survived.
The supply of alexandrite from the Urals was virtually exhausted by the early part of the 20th century. While similar stones were discovered in other mines, they did not exhibit the telltale, vivid green-to-red color change displayed by the original Ural gemstones. It appeared that real alexandrite rings would simply become very expensive and difficult-to-find pieces from the past.
The situation changed drastically, however, in 1987. That’s when a new deposit of alexandrite was discovered in a Brazilian mine known as Hematita; the stones weren’t quite as perfect as the 19th century Russian gemstones, but they were very close with outstanding color richness and clarity. Most importantly, they exhibited the vivid green-to-red color change so important to high-quality alexandrites – unlike stones coming from places like Asian nations like Sri Lanka or African countries like Zimbabwe, which typically have a yellowish or brown undertone to their colors, or barely change color at all.
Once again, however, the supply seemed to become exhausted quickly, although some claim the cause was a dispute over mining rights rather than an actual depletion of the alexandrite deposits. In any event, very few new Brazilian alexandrites have hit the market in recent years and the stone remains extremely rare. Some quality stones have come from southern Tanzania over the last two decades, but in very small quantities; today the best source for top-quality, genuine alexandrite rings is once again Russia, because of increased trade between that country and western nations.
The Story Behind Alexandrite’s Colors
If you know anyone fortunate enough to have an alexandrite engagement ring (or an alexandrite wedding ring, for that matter), they’ll tell you that they receive many more compliments than their friends with diamond rings, no matter the respective sizes of the stones. That’s because of the unique and striking color-changing features of the rare gemstone. In daylight, a real alexandrite ring will have a green (or bluish-green) color, but under incandescent light, the stone will show as red (sometimes a bright raspberry red, sometimes a softer shade, and sometimes even a purplish-red).
The reason for this unique change in colors can be summed up in one word: chromium. However, a bit of science is needed to understand why that element is so important. Alexandrite is classified as a “chrysoberyl”, which is a mineral primarily composed of beryllium aluminum oxide and impurities like titanium and iron. The rare element chromium usually doesn’t occur in nature alongside beryllium; however, in the very unlikely event that the two are present together in the right environment for geological growth – and if there’s no silica present at the same time – a chrysoberyl becomes alexandrite. A chrysoberyl will only have the green-to-red color characteristic if chromium is included (if you’re wondering what silica has to do with this, its presence would turn the mineral into an emerald instead of an alexandrite).
That’s why alexandrite is so rarely discovered and so highly prized – the conditions necessary for its creation almost never occur in real life. In fact, a genuine alexandrite ring is valued in somewhat of a different way than most gemstone rings; along with its overall cut, clarity, color and carats, alexandrite’s value is very closely tied to the strength of its changes in color.
There’s one other scientific oddity about these stones. They are expected to have small inclusions since they’re classified as a type II gemstone, and that can lead to even rarer types of alexandrite which exhibit a cymophane effect (a floating reflection seen to move when the gemstone is rotated) or a cat’s eye effect (similar to cymophane, but with a thin band of reflected light). Any cat’s eye stone is highly desirable, and these types of alexandrites are among the most sought-after in the world.
It may seem surprising for such a valuable piece of jewelry, but an alexandrite ring is one of the easiest-to-maintain pieces of jewelry you can own. It is tough, hard (measuring 8.5 on the Mohs scale of mineral hardness) and durable, and doesn’t require any special care even with everyday wear. The largest Russian alexandrite ever discovered is housed at the Smithsonian Institution in Washington; it is a nearly-perfect specimen weighing in at 66 carats, and it is considered priceless.
Alexandrite in the Real World
By now, you may be intrigued enough with the story of alexandrite – or the exquisite beauty of the stone – to wonder if it’s possible to actually own one.
The answer is probably obvious, even before you’ve learned that real Russian alexandrite stones weighing more than a carat are even more expensive than equivalent-sized emeralds, sapphires or rubies. The very finest alexandrite rings generally fall into the “if you have to ask, you can’t afford it” category; many list at well over $100,000.
However, that doesn’t mean you should abandon all hope. For example, if you’re considering purchasing an alexandrite engagement ring, it’s a (theoretically, anyway) once-in-a-lifetime purchase. Many people who have the money feel that sort of expenditure is worth it – after all, an enormous number of very expensive diamond engagement rings are sold daily – while many others save up for months or years to buy the perfect engagement ring. Here are some of the particulars to help you decide.
Generally speaking, quality alexandrite costs anywhere between $5,000 and $10,000 per carat, with some one-carat stones costing as much as $15,000; you can compare that with quality diamonds which average between $3,000 and $10,000 per carat (although they can also go much higher). Obviously, the alexandrite engagement ring will cost more than its diamond equivalent, but they’re still in the same overall ballpark. (The news gets better; read on).
To take it a step further, you can make “compromises” in order to lower the price of the ring. We’ve already mentioned that the “4 C’s” are considered in valuing alexandrite, along with the stone’s color change characteristics. In the same way that you might opt for a lesser cut or lower clarity in a diamond, you can make the same compromises for an alexandrite. However, you can also choose a stone with slightly less vibrant colors or less of a color change, in order to lower the price of your ring.
The most expensive alexandrites will be bright green in daylight, looking much like an emerald; in incandescent light, they’ll look very much like a dark ruby. If you’re willing to settle for a lighter green or more of a bluish-green in sunlight, and a lighter red or purplish color once it changes, the price of your gemstone will be lower. Similarly, you can consider how much of the stone actually changes color with the light. If less than 30% of an alexandrite changes color, it’s not even considered an alexandrite, it’s called a “color changing chrysoberyl”. But once more than 30% of the stone changes from green to red, you have an alexandrite and the price you’ll pay depends on the percentage of color change.
Now, here’s some of the good news we promised. Most alexandrites are naturally less than a carat in weight, and you can easily find good-quality stones with nice color changes in engagement rings (or in alexandrite wedding rings) for $5,000 or less. That won’t help if having a huge rock on her finger is important to the bride, but if the enticement of a genuine alexandrite ring is enough to compensate, it’s a gift she’ll never forget.
Two cautionary notes, though, for those with money to burn. First, if you’re looking to have an alexandrite custom-cut for a specific setting, be prepared to pay even more than we’ve talked about. In order to maintain maximum color changes and brilliance the gemstone is extremely challenging to cut properly, so that will add quite a bit to an already-steep price tag. Second, since most stones are normally less than a carat, larger ones are very rare and carry the prices which go along with rarity; it’s not unusual for alexandrite engagement rings to cost well over $100,000. A vintage alexandrite ring can cost even more. Nice neighborhood, if you can afford it.
Of course, there’s always the option of buying a synthetic, or lab-created, alexandrite ring. Even if you don’t want to consider the possibility, it’s good to know the characteristics of synthetic stones before you go shopping for the real thing – to lower the chances that you get fooled.
There are several ways that labs create what they call alexandrite, and unfortunately not all of the synthetics are easy to spot. Some, however, are. Stones created by what’s called the “crystal pulling” method usually look extremely clean (unlike real alexandrites) and when viewed under a magnifying glass, the inclusions look like raindrops. And many stones sold as alexandrite are really lab-made “color-change corundum” (synthetic sapphires) which can easily be spotted. Instead of changing from green to red, they change from purplish-blue to pinkish-purple without ever showing the characteristic green color in sunlight, because the stones contain vanadium instead of chromium.
More difficult is telling whether a gemstone is really a synthetic alexandrite grown by the “flux method”. This is a very relatively expensive process, and it creates stones which can usually only be differentiated from the real thing by an expert. In fact, there’s one case where the two major labs which certify gemstones, GIA and AGL, came up with different conclusions on a stone submitted for evaluation; GIA certified it as natural, while AGL later discovered it was really lab-created.
This could also be our last bit of good news, however. Since synthetics grown by the flux method so closely resemble the real thing, it’s possible to “settle” for one of these non-genuine alexandrite rings at a much lower price, and have your very own alexandrite engagement ring at a cost you can afford – at least until you’re able to put up the big bucks for a real alexandrite ring you can treasure and show off forever.