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.
