TL;DR: alexandrite is a rare gemstone known for changing colour, usually appearing greenish in daylight and reddish or purplish under warm light. It is hard enough for a ring, but natural stones of good quality are scarce and costly, and many alexandrites sold today are lab grown. Ask exactly what you are being sold, and see the stone in different lights. Pieces start from £600.
The colour change
The famous feature of alexandrite is that its colour appears to shift with the light. In daylight or fluorescent light it tends to look green or bluish green, and in warm incandescent light it tends to look red or purplish. How strong the change is varies from stone to stone, and a strong change is what people value most.
Is it hard enough for a ring?
Alexandrite is a hard and durable gemstone, harder than many coloured stones, and suits regular wear when set sensibly. It is still not as hard as a diamond, so a protective setting is wise. Our guide to the Mohs hardness chart for ring stones explains how stones compare.
Natural or lab grown
Natural alexandrite of fine quality is rare, and larger stones with a strong colour change are rarer still. Lab grown alexandrite exists and is often easier to find. Be careful with the word alexandrite in descriptions. Some stones sold under similar names are other materials that imitate the effect. Ask for the stone to be described in writing, including whether it is natural or lab grown, and whether it has been treated.
Judging a stone
- Look at the stone in daylight and in warm indoor light.
- Check how strong the change is, not just how pretty each colour is.
- Look at clarity. Natural stones often have visible inclusions.
- Ask what the report says and what it does not.
Why photographs can mislead
Because the colour depends on the light, a photograph shows only one moment. A stone photographed in bright daylight may look quite different from the same stone under a restaurant lamp. Ask for video in different lights, and ask us to describe the change in words. A good seller will happily show you both.
Other colour change stones
Alexandrite is the best known colour change gemstone, but it is not the only one. Some sapphires and garnets also shift colour between daylight and warm light, often from blue to purple or from green to pink. These can be easier to find and suit a different budget. Our guide to colour change sapphires explains how they compare, and we are happy to show you both side by side on video.
Choosing a setting
A bezel or a well protected claw setting suits alexandrite, and a simple design lets the colour take centre stage. Our guide to best settings for sapphire explains the same principles for coloured stones. Think too about the metal. Yellow and white metals each change how the stone looks.
Birthstone
Alexandrite is a birthstone for June, which gives it extra meaning for some people. See our guide to birthstones by month as engagement rings.
Working with us
Alexandrite takes time to source, so tell us early. We work by video consultation and message, send sketches and CAD renders, and make nothing until you approve the design in writing. Standard making time is 5 to 6 weeks, varying with your location and how busy we are, and stone searching can add time. Overseas, the customer pays import duty and tax, and delivery is insured and tracked with FedEx.
Frequently asked questions
Does alexandrite really change colour?
Yes, to varying degrees. Check how strong the change is.
Is alexandrite durable?
It is hard and suits rings with a protective setting.
Is it rare?
Fine natural stones are. Lab grown stones are easier to find, and we say which is which.
Can I see it in different lights?
We can share photographs and video in different lighting.
Are there cheaper colour change stones?
Some colour change sapphires and garnets can suit a smaller budget, so ask us to compare.