Shades of Wonder
Among the many marvels of the gemstone world, Alexandrite holds a special place with its extraordinary ability to change color based on the lighting environment. This phenomenon not only captivates the imagination but also significantly enhances the gemstone’s value and appeal. In this blog post, we’ll dive deep into what drives this mesmerizing feature, how to assess it, and its impact on the value of Alexandrite.
What Drives the Colour Change in Alexandrite?
The color change characteristic of Alexandrite is due to the presence of chromium ions in the crystal structure, which absorb light in a specific way. Under daylight or fluorescent light, Alexandrite appears green to bluish-green. This shifts to a red to purplish-red under incandescent light due to the differential absorption of light in the yellow portion of the spectrum, allowing more red and blue-green wavelengths to be transmitted.
Assessing the Quality of Colour Change
The value of an Alexandrite stone is largely determined by the quality of its colour change, which is the most coveted trait. Here’s how the quality of this phenomenon can be assessed:
- Intensity of the Colour Change: The more dramatic and complete the shift from green to red, the higher the quality and value of the stone. A strong, vivid colour change is a key marker of a fine Alexandrite.
- Colour Saturation: High-quality Alexandrite should display deep and intense colours in both green and red states. Stones that exhibit weak or pale colours in any light tend to be less valuable.
- Consistency and Uniformity: The colour change should be uniform across the entirety of the stone. Patchiness or zones of different colours can detract from the gem’s overall appearance and desirability.
Comparing Colour Ranges
Not all Alexandrites are created equal, and their desirability depends heavily on the specific shades they display. Here are some colour comparisons to keep in mind:
- Ideal Colour Change: The most sought-after Alexandrites show a vivid green to bluish-green in daylight and a deep red to purplish-red in incandescent light.
- Less Desirable Colours: Some Alexandrites may show less preferred colour changes, such as yellowish-green in daylight moving to brownish-red under incandescent light. These stones, while still valuable, are typically priced lower than those with more desirable colour changes.
Tips for Purchasing Alexandrite
When considering purchasing Alexandrite, here are some tips to ensure you choose a stone that meets your expectations:
- View in Different Lights: Always observe the Alexandrite under multiple lighting conditions to fully appreciate and evaluate its colour change.
- Certification and Documentation: Ensure that the gemstone comes with a certification from a reputable lab that confirms the nature and quality of the color change.
- Consult with Professionals: Working with knowledgeable jewellers or gemmologists can help guide your purchase, especially when assessing such a unique characteristic as colour change.
Conclusion
The colour-changing ability of Alexandrite makes it one of the most fascinating and sought-after gemstones in the world. Understanding and appreciating this unique feature can greatly enhance your experience of selecting and owning a piece of this magical gem. Whether you are an investor, collector, or someone looking for a unique piece of jewellery, knowing what makes the colour change in Alexandrite so special will help you make informed decisions and find a gem that truly meets your desires.