Sold out
Color Change Gemstones
Color-change gemstones look one color in daylight and another under warm artificial light, most often green to blue-green outdoors and red to purple under incandescent bulbs or candlelight. The best-known examples are alexandrite (BeAl2O4, a chrysoberyl) and color-change garnet ((Mg,Mn)3Al2(SiO4)3).
Read more ↓16 products
- Sold out
- Sold out
- Sold out
- Sold out
- Sold out
- Sold out
- Sold out
- Sold out
- Sold out
- Sold out
Gemstone guide
Color Change Gemstones
About color-change gemstones
The effect happens when a stone absorbs light in the middle of the spectrum and lets through red and blue-green light in nearly equal amounts. Daylight is richer in blue and green, so the stone looks green; incandescent light is richer in red, so it looks red. Chromium or vanadium usually cause it. Besides alexandrite and garnet, some sapphires, spinels and diaspores also change color.
What you'll find in this collection
All stones here are untreated. You'll find small faceted alexandrites from Russia and color-change garnets from Africa, Madagascar and Tanzania, in rounds, ovals and marquises from about 0.05 to 1.2 carats, each photographed in different light so you can see its own change.
How to recognise color-change gemstones
Compare the stone in daylight and then under a warm bulb or candlelight; the strength of the change varies from stone to stone, from a subtle shift to a striking one. Alexandrite is also strongly pleochroic, showing different colors in different directions under the same light, while garnet is singly refractive and does not.
Caring for color-change gemstones
Alexandrite and garnet are both hard and have no easy cleavage, so they suit everyday jewelry. Clean them with warm soapy water and a soft brush.
Every stone is natural, and each listing gives its weight, size, origin and treatment, with photos of the actual stone.