Color-change garnet is a rare and fascinating variety of garnet that exhibits a remarkable phenomenon where its color changes under different lighting conditions.
Color-change garnets exhibit a unique optical phenomenon known as the alexandrite effect, where the gemstone appears to change color depending on the type of lighting it is viewed under. Typically, color-change garnets display one color under daylight or fluorescent lighting and a different color under incandescent lighting or candlelight.

The most common color-change combination for garnets is from blue-green or greenish-blue in daylight to purplish-red or reddish-purple in incandescent light. However, some color-change garnets may exhibit other color combinations, such as brownish-green to pinkish-brown or grayish-green to reddish-brown.

Color-change garnets are primarily composed of the mineral species known as garnet, which encompasses several different varieties. The color change in these garnets is typically due to the presence of trace elements such as chromium and vanadium.

Garnets, including color-change garnets, are relatively hard gemstones with a Mohs hardness ranging from 6.5 to 7.5. This makes them suitable for use in various types of jewelry, although care should still be taken to avoid harsh chemicals and sharp blows.

Color-change garnets have been found in various locations around the world, including Tanzania, Madagascar, Sri Lanka, Russia, and the United States (specifically California and Idaho). Each location may produce color-change garnets with unique color combinations and characteristics.

Color-change garnets are highly prized by gemstone collectors and enthusiasts for their rarity and optical phenomenon. They are often used as center stones in rings, earrings, and pendants, where their unique color-changing ability can be showcased and appreciated.

The value of color-change garnets is influenced by factors such as the intensity and rarity of the color change, as well as the overall quality of the gemstone including clarity, cut, and size.

Overall, color-change garnets are cherished for their captivating optical phenomenon and beauty. Their rarity and unique color-changing ability make them a sought-after choice for those seeking something truly special and unique in their gemstone jewelry.