Alexandrite! A June birthstone is called the chameleon stone due to its ability to look green or red depending upon what light it's viewed in. Enhances creativity and allows alignment between the physical and spiritual realms. Great for intuitive work!
A stone with phenomenal color-changing ability, alexandrite is one of the birthstones for June, along with pearl and moonstone. The stone was discovered in the 1830s and was named in honor of Czar Alexander II.
Regional Variations in Alexandrites
Brazilian alexandrites tend to have pale colors, pale blue-green to pale mauve. However, finer gems have been found recently in limited quantity.
Cat’s Eye Alexandrites. Alexandrite is a variety of the gem species chrysoberyl, well-known for its chatoyancy or “cat’s eye” effect when cabbed. As members of this species, alexandrites can also show a cat’s eye effect. However, such gems are quite rare.
Sri Lankan alexandrite often appears deep olive green in sunlight, whereas Russian stones appear bluish-green in sunlight.
Zimbabwean gems show a fine, emerald-green color in sunlight but are usually tiny. If clean, they weigh under 1 carat. The color change in Zimbabwean gems is among the best known, but large, clean stones are virtually unobtainable from the rough from this locality.
Alexandrites have two primary value drivers.
First, the closer the colors to pure green and red, the higher the value. Second, the more distinct the color change, the higher the value. Alexandrites can exhibit everything from 100% to just 5% color change. Thus, the most valuable gems would have a 100% color shift from pure green to pure red. Blue greens and purplish or brownish reds hold less value.
Clarity also plays a significant role in grading. As is the case with a majority of gems, most naturally occurring alexandrite isn’t clean, face table material. Most are best suited for cabbing. However, an alexandrite’s color change has more effect on its value than its clarity. For example, take two alexandrites of equal size. One gem is eye clean, with a 50% greenish blue to brownish-red color change.
The color change gemstone phenomenon can occur under a variety of lighting types. When grading an alexandrite’s color change, gemologists consider the stone’s color in natural sunlight as the baseline. Thus, the classic alexandrite color change is green in sunlight and red in incandescent light.
The largest known faceted alexandrite, a 65.7-ct green/red color change stone from Sri Lanka, resides at the Smithsonian Institution. The largest Russian gems weigh about 30 carats. However, the vast majority of alexandrites weigh under one carat. Stones over five carats are very rare, especially with good color change.
With a hardness of 8.5, alexandrite makes a very durable stone suitable for any jewelry setting. Nevertheless, take care when faceting the stone. Alexandrite is still sensitive to knocks and extreme heat.
These gems have no special care requirements. You can clean them mechanically, per the instructions of the system used. Of course, you can also wash them with warm, soapy water and a brush.