How to Identify a Genuine Alexandrite: A Guide to Spotting the Real Deal
Alexandrite is a remarkable and rare gemstone, celebrated for its unique ability to change colour under different lighting conditions.
In short: Genuine alexandrite (chrysoberyl variety, Mohs 8.5) shows distinct colour-change: green in daylight, red/purple under incandescent light. Imitations (synthetic corundum, colour-change garnet) don't show the same intensity of shift. Always insist on a GIA or AGL identification report; expect £4,000-£15,000/ct for fine 1ct natural alexandrite.
This captivating feature, combined with its scarcity, makes alexandrite highly sought after and, so a target for imitations.
If you're considering acquiring this gem, it's essential to know how to distinguish a genuine alexandrite from synthetic or simulated versions.
In this guide, we'll explore the key characteristics of authentic alexandrite and provide practical tips to help you identify the real deal.
The Unique Colour Change of Alexandrite
One of the most distinctive features of alexandrite is its colour change phenomenon.
In natural daylight or fluorescent light, genuine alexandrite typically appears green to bluish-green.
Under incandescent or candlelight, it transforms to a purplish-red or reddish hue.
This dramatic shift is due to the complex way alexandrite absorbs light, influenced by the presence of chromium ions in its crystal structure.
When assessing an alexandrite's colour change:
- Observe the Stone Under Different Light Sources: View the gemstone in natural daylight and then under incandescent light to witness the colour transition. A genuine alexandrite will exhibit a noticeable and distinct change.
- Evaluate the Intensity of the Colour Change: High-quality natural alexandrites display a strong and clear colour change. Stones with weak or minimal shifts may be of lower quality or possibly synthetic.