Alexandrite

The dramatic color change in alexandrite is caused by the presence of trace amounts of chromium ions within the chrysoberyl crystal structure. This specific chemical impurity allows the stone to absorb light differently depending on the light source, appearing green in daylight and shifting to a red or purple under incandescent light. This phenomenon is known as the alexandrite effect.

The finest and original alexandrite was discovered in the emerald mines of the Ural Mountains in Russia in the 1830s. It was named after the future Tsar Alexander II because the green and red colors perfectly matched the Russian imperial military colors. Unfortunately, the Russian mines were largely depleted by the late 19th century, making high-quality stones incredibly rare today.

Yes, today the most significant commercial sources of alexandrite are mines in Brazil, specifically in the states of Minas Gerais and Bahia. Sri Lanka and East Africa, particularly Tanzania and Zimbabwe, also produce alexandrite, though the color change is often less dramatic. Brazilian alexandrite is highly prized and can exhibit a very distinct blue-to-purple shift.

Alexandrite was officially added as one of the modern birthstones for the month of June, alongside pearl and moonstone. Because of its extreme rarity and unique optical properties, natural alexandrite is considered the most expensive and coveted of the three June birthstones. Many jewelers use lab-created alexandrite as a more affordable alternative for birthstone jewelry.