Beware any auction selling "genuine" alexandrite.

There are currently very little alexandrite stones being mined and as such are valuable gems. Due to high demand over this relatively small supply, scientists now can manufacture less-quality imposters. This stone can be imitated by either synthetic spinal or in great quantities by synthetic corundum. Both of which are commonly mistaken as synthetic alexandrite.

A few ways to identify such fakes are:
Alexandrite dose not change 100% in color, but rather closer to 75%. Remember imperfections are a form of natural beauty, so large, flawless perfect clarity gems don't really exist. However if the Alexandrite is real and ways over 1 carat, you've got one extremely rare and very valuable stone. Real alexandrite is worth tens of thousands of dollars!

What is alexandrite?

The gemstone of June, alexandrite was discovered in 1830 and is named after Czar Alexander II, Prince of Russia. Though most commonly mined in both Russia and Brazil, other origins of alexandrite include: Sri Lanka, Madagascar and Tanzania.

Considered a "semiprecious gemstone," alexandrite is a rare member of the Chrysoberyl mineral family. The diverse variety of color change its most well known visual quality, directly representative of the light illuminating it. The value of alexandrite is consistent with such color change. The higher the range of color and deeper the saturation, the more valuable the stone.

 Quality alexandrite should resemble a vivid green in daylight and purple-red or deep purple in tungsten light without any trace of undesirable brown.

Here is a quick reference of color changes in real alexandrite:
- red to green in fluorescent light
- green or blue-green in daylight
- blue in direct  sunlight
- red-purple, purple and deep purple in tungsten and "artificial light"
- red in candlelight

This color and surface quality are derived by the presence of oxide  in chromium.

Here are a few technical facts regarding alexandrite:
- Reflective Index: 1.741 - 1.760
- Chemical Composition: BeAl2O4
- Hardness: 8.5
- Density: 3.73
- Crystal Structure: orthorhombic

Alexandrite is a valuable iridescent semiprecious gemstone. Its reflective color can change from red to green to blue to purple dependent on the quality and angle of light illuminating it. Due to its high demand and its relatively small supply, scientists now can manufacture less-quality imposters. Such fakes are often too perfect to be true and do not hold and retain the monetary value that real alexandrite stones do. If you plan to purchase this truly amazing gem, please consider these variables so you end up with what you really paid for and not an imitation.