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Alexandrite Birthstone stone is a gemstone that changes colors depending on the light source. This makes it very unique and beautiful. How is it so special? In this blog we are going to examine this and know the true essence of alexandrite color change.
Alexandrite's color-change effect is truly magical.
The color-change effect of alexandrite is truly magical, as it can go from green to red, blue to purple, red to yellow and even blue to red or purple to green. It's actually quite rare for any gemstone to have such an extensive array of colors. This means that if you want a ring with this incredible feature, your options are plentiful. If you find one that fits your finger and budget, take it home with you!
Alexandrite color-change is caused by its optical properties emerging from chromium impurities
The color-change effect is caused by the optical properties of alexandrite stone birthstone. The gemstone is a form of chrysoberyl, which is itself a beryllium aluminium oxide mineral. Chrysoberylscan be found in many different shades, but the most prized specimens are greenish-yellow or brownish-green with an excellent color change between these two colors. Alexandrite must have excellent color change and rich saturation to be considered truly valuable.
You will see an alexandrite stone's true colors in natural light.
You will see an alexandrite stone's true colors in natural light. Tungsten (incandescent) lamps produce a much warmer light than daylight, since they emit infrared radiation (heat). In contrast, daylight contains ultraviolet radiation, which causes alexandrite stones to appear redder or bluer depending on their chromium content and trigonal structure.
Change of color can be used to identify natural alexandrite from synthetic varieties.
You may have heard that alexandrite changes color when looked at in different kinds of light. This is true, but how do you know if the stone you’re looking at is natural or synthetic?
A great way to determine if an alexandrite has been treated with heat and irradiatedis to observe its color-change effect in different types of light. Most synthetics will show no color-change effect regardless of the type of lighting used. A true natural alexandrite will exhibit various colors depending on whether it’s viewed under daylight or incandescent light sources.
Given its rarity, alexandrite's color-change effect is unlike anything you'll see in other gemstones.
Given its rarity, alexandrite's color change effect is unlike anything you'll see in other gemstones. It's not caused by the light source, nor does it have to do with the stone's shape. Instead, it's a natural phenomenon that occurs when certain chromium impurities are present during growth of the stone and/or during heating after cutting and polishing.
The alexandrite color change effect is also known as reversible photochromism or reversible pleochroism (because it can be seen through different angles). This means that when viewed at different angles or under different lighting conditions (such as direct sunlight vs indoor lighting), an alexandrite will appear greenish-blue and purple or red respectively.
