You may have heard of the phenomenon known as color-change, which is an evident visual effect seen in some species and varieties of gemstones. Today, we'll introduce you to some of the natural world's spectral mood stones, that seemingly transform in the ambience of different environments.



Color-change is most popularly noted to be a defining trait of the gemstone known as alexandrite. This stone is a variety of the chrysoberyl species, and remains to be the most expensive variant per equal quality characteristics. Alexandrite in its finest forms, can change from ruby-red to emerald-green depending on whether you view it under incandescent light (candle-light) or normal daylight. Top qualities can command tens of thousands of dollars, although synthetic variants (man-made versions) also do exist.



Next up, we have a variety of diamond that not many people are familiar with. These color-changing rarities have been termed as "chameleon diamonds" and change their color due to a combination of light and heat. Many are a subtle green, but can change into a vibrant yellow or brownish yellow when subjected to the said conditions. These diamonds are quite rare, and not very much is documented about their nature. Still, it's an interesting quirk to have, especially for the world's most famous gemstone.



Thirdly, we have color-change sapphire. Sapphire as you might already know, does not only come in the vivid blue colors that we usually associate them with. They belong to the mineral species known as corundum (along with their cousin- the ruby). While blue sapphire is colored by a charge transfer between trace atoms of iron and titanium, the presence of other elements can also induce a wider variety of colors in the mineral species. The presence of certain elements like chromium and vanadium have been associated with the color-change phenomenon seen in natural sapphires. Synthetic or man-made corundum is usually doped with different amounts of vanadium to create artificially grown color-change sapphires that can shift from a reddish purple at best, to a violetish blue in opposite lightings.



Be aware that aside from synthetic counterparts, glass can also be manufactured with trace elements that allow for color-change. This makes it possible to create imitations of these phenomenal stones, so have your gemologist take a look at your gems, to give an better opinion on the validity of their identities.

Both ruby and emerald are among the most popular colored gemstones widely traded in today's society. Both have an allure that deeply connects with buyers, through the vibrancy of their corresponding colors; a crimson red and a vermillion green. Many who collect gemstones have at least a few specimens of each in their prized jewelry boxes, but not all know of a stone that can change from fiery reds in the evening, to verdant greens in the morning.



Alexandrite is the color-changing variety of chrysoberyl. It's remarkable composition and structure allows it to display a fascinating phenomenon that merges the appeal of two different hues. The presence of light plays a big part in alexandrite's transformative elegance. Incandescent light- such as the warm orange glow of burning candles, can make alexandrite's color turn a fiery red. It is often called the evening ruby, a nickname that has stuck for several decades since its popularity took flight.



In the morning, or much more specifically, under the cooler glow of natural sunlight or fluorescent light, most alexandrite specimens display a fine green that possesses just a touch of blue. The best samples of the stone show a stark, contrast between their two hues, creating the dual appeal of having both a ruby and an emerald (although chemically speaking, these belong to entirely different species).



Very fine stones are sold at auction for tens of thousands of dollars, and connoisseurs who are familiar with its name, offer to pay quite the hefty fee for a beautiful alexandrite.

It's accepted knowledge though that, no matter how rare or fine the alexandrite specimen, even the best ones will not completely match the saturation and purity of either ruby's reds or emerald's greens. Though despite this, some stones come pretty close, displaying colors convincing enough to fool onlookers into thinking the stone was actually something else.



Chrysoberyl, the gem species housing alexandrite, is also famous for having a cat's eye variety. These stones display chatoyancy, where a thin, sharp band gracefully moves across a domed surface, created by multitudes of parallel needles. Sometimes, color-changing alexandrite can also be fashioned with a cat's eye, displaying two beautiful visual phenomena at the same time.