# Alexandrite

> Alexandrite shifts from bluish green to purplish red depending on the light; a very rare and costly gem (8.5 on Mohs), and a June birthstone.

- Source: https://www.711grados.com/en/alexandrite/
- Language: en
- Note: This entry was drafted with the help of AI and is pending review by the author.
- Published: 2026-09-02
- Updated: 2026-09-11
- Translation (es): https://www.711grados.com/es/alejandrita/
- Author: Sandra Sánchez
- Site: 711 Grados (https://www.711grados.com/)

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Alexandrite is a variety of chrysoberyl with a unique phenomenon: it looks bluish green in daylight and red or purplish under an incandescent bulb. It was discovered in Russia in the 19th century.

## Properties

- **Composition:** beryllium aluminum oxide with chromium.
- **Hardness:** 8.5 on the Mohs scale.
- **Color:** changes from bluish green to purplish red depending on the light.
- **Origins:** Russia (Urals), Brazil, Sri Lanka, India and Tanzania.
- **Treatments:** natural ones are not usually treated; many synthetic ones exist.

## Uses in jewelry

- Collector's jewelry.
- Rings and pendants with a center stone.
- June birthstone.

## Pros and cons

### Advantages

- Very hard and durable.
- Extraordinary color change.
- Highly prized by collectors.

### Limitations

- Quality natural ones are extremely expensive.
- Synthetics and imitations abound.
- A certificate is necessary.

## Care and cleaning

- Clean with lukewarm water and mild soap.
- Tolerates ultrasonic if well set.
- Store apart from other stones.

## See also

- [Gemstones in jewelry](https://www.711grados.com/en/gemstones-in-jewelry/)
- [Sapphire](https://www.711grados.com/en/sapphire/)