Alexandrite changes colour because of tiny amounts of chromium inside it. In daylight it looks green or bluish-green. Under warm indoor light, like a lamp or a candle, it turns red or purplish-red.
This shift is called the alexandrite effect, and it is why people call the stone "emerald by day, ruby by night". You can see real colour-change stones in our alexandrite collection.
What is alexandrite?
A special kind of chrysoberyl. Chrysoberyl is a mineral made of beryllium, aluminium and oxygen. Its formula is BeAl₂O₄.
Chromium makes the difference. Ordinary chrysoberyl does not change colour. Alexandrite contains a small amount of chromium, and that is what lets it shift.
A Russian discovery. Alexandrite was first found in the Ural Mountains of Russia in the 1830s. It was named after Alexander II, who later became the Tsar of Russia.
Mistaken for emerald. The miners first took it for emerald. Some even thought they had found two different stones, one green and one red, before they learned it was the same rare gemstone changing colour.
Why does alexandrite change colour?
Most gemstones keep the same colour in any light. Alexandrite is different because of the way its chromium handles light.
- Chromium takes aluminium's place: chromium atoms replace some of the aluminium atoms in the crystal.
- Light gets sorted: those chromium atoms absorb some colours of light and reflect others.
- The light source decides: daylight and indoor light contain different amounts of each colour, so the stone reflects a different mix in each.
Without chromium, alexandrite could not shift from green to red. In emerald, the same element gives a strong green. In alexandrite it does something rarer.
In daylight: green or bluish-green
Sunlight is rich in blue and green light. The chromium absorbs some of the red, so your eyes see a green or bluish-green stone.
Under warm light: red or purplish-red
Light bulbs, candles and firelight have more red and yellow light. Now the chromium absorbs more of the green and blue, so the stone looks red or purplish-red.
Other bulbs, other shades. Under different lamps it can also look purple, pink or even blue.
What is the alexandrite effect?
The alexandrite effect is the name for this colour change. Only a few gemstones can change colour like this, and none of them is as famous as alexandrite.
How to see the colour change yourself
- Go outside: look at the stone in sunlight. It should look green or bluish-green.
- Come inside: hold it under a warm lamp or candlelight. It should turn red or purplish-red.
- Move it back and forth: switch between the two lights and watch the shift happen in your hand.
Is alexandrite alive?
No, but it is easy to see why people ask. Alexandrite does not breathe, grow or move. What it does is react to light, a bit like a living thing reacts to its surroundings.
Like a chameleon. A chameleon changes colour to match where it sits. Alexandrite matches the light instead: green like trees in daylight, red like fire in warm light.
Never the same twice. You can look at it many times in one day and see many different shades. That is why it has been called "the stone of transformation", "the living gem" and "nature's colour-changing wonder".
Why is alexandrite so rare?
Alexandrite needs a perfect mix of elements to form, and nature rarely provides it.
- It needs chromium: chromium is not common in the earth's crust, and it must be present in just the right amount.
- It needs beryllium and chromium together: these two elements rarely appear in the same place.
- Not every stone shifts well: most natural alexandrite found today is small, with a weak colour change.
Finding a large, high-quality stone with a clear, dramatic colour change is very difficult. That is why fine alexandrite is one of the most valuable gemstones in the world.
Where is alexandrite found?
Alexandrite comes from only a few places in the world:
- Russia: the original and most famous source, known for the strongest green-to-red shift.
- Brazil: one of the biggest sources today, with bright, vibrant green stones.
- Sri Lanka: known for lighter colours and a softer colour change.
- India: has deposits, but they are very rare.
- Madagascar: a newer source with good-quality stones.
- Tanzania and Zimbabwe: some alexandrite, but not in large amounts.
Alexandrite price: why is it so expensive?
It is one of the most expensive gemstones in the world. A high-quality alexandrite can cost more than a diamond, and even small stones can cost thousands of dollars.
- Strength of the colour change: a strong, clear shift is worth the most.
- Size and clarity: the bigger and clearer the stone, the higher the price.
- Origin: Russian alexandrite is the most expensive because it has the best colour change.
What is the rarest colour of alexandrite?
The rarest stones show a deep green or blue-green in sunlight and a strong red or purple-red in soft light. Stones with a lighter or weaker change are less rare and less valuable.
Why is some alexandrite cheap?
- The colour change is weak.
- The stone is small or has flaws.
- It is lab-made, not natural.
Natural vs lab-grown alexandrite
Natural alexandrite forms deep in the earth over millions of years. Lab-grown alexandrite is made in a laboratory. Both can look very similar, but natural stones are far rarer and more valuable.
Most of what is sold is not natural. Most alexandrite sold today is either synthetic (lab-made) or treated to enhance its colour. Because real alexandrite is so expensive, many people choose synthetic stones, which look the same.
How to tell if alexandrite is real
Because alexandrite is rare and costly, many fake stones are sold as real ones. Here is how to check:
- Colour change: real alexandrite changes from green to red in different light. If it does not change, or the colours look artificial, it is probably fake.
- Magnifying glass: a real stone usually shows natural patterns inside.
- Price: real alexandrite is very expensive. If it is too cheap, it is likely fake.
- Certificate: ask for a report from a trusted gem lab such as GIA.
- Expert check: the surest way is to have a jeweller or gem expert test it.
Alexandrite meaning and beliefs
The ideas in this section are traditions and beliefs, shared for interest. They are not proven facts.
Balance and change. Because it shifts from green to red, alexandrite is seen as a symbol of balance: day and night, calm and excitement. Many people wear it as a reminder that life changes, just like the stone.
Two moods. Some people say the green side feels calm and fresh, like a forest, while the red side feels warm and strong, like a sunset.
What is alexandrite good for in tradition?
- Luck and success: worn as a lucky charm for fortune in life and business.
- Confidence: said to give courage to face challenges.
- Clear thinking: linked with focus and better decisions.
- Emotional balance: believed to bring happiness and joy to the wearer.
- Creativity: artists like it as a stone of new ideas and imagination.
- Love and harmony: linked with good relationships.
- Protection: thought to keep away bad luck and negative energy.
Old traditions and nicknames
- "Friday's gem": it is said to bring good luck on Fridays.
- Travel and home: it was believed to protect travellers and bring peace to the home.
- Royalty: in Russia it was thought to stand for power and royalty.
Alexandrite jewellery and daily wear
Because it is so rare, alexandrite is mostly used in fine jewellery:
- Rings: often set in gold or platinum.
- Pendants: many people wear one as a lucky necklace.
- Earrings and bracelets: a stylish way to show off the colour shift.
Hard enough for daily wear. Alexandrite is 8.5 on the Mohs scale, harder than most gemstones. You can wear it every day, but it can still be scratched by harder stones, damaged by harsh chemicals, or lost from a loose setting.
How to care for alexandrite
- Clean gently: use a soft brush and mild soap.
- Avoid harsh chemicals: keep it away from strong cleaning products.
- Store it safely: wrap it in a soft cloth or keep it in its own spot in a jewellery box, away from harder gems.
- Check the setting: if you wear it daily, make sure the stone is held firmly.
FAQs
Is alexandrite stronger than diamond?
No. Diamond is the hardest gemstone, at 10 on the Mohs scale. Alexandrite is softer, at 8.5, so a diamond can scratch it.
Is alexandrite rarer than diamonds?
Yes, much rarer. Diamonds are found all over the world, while alexandrite comes from very few places, and top-quality alexandrite is rarer still.
What is the rarest gemstone in the world?
Painite is often named the rarest, said to be over 1,000 times rarer than diamonds. Alexandrite, red beryl, black opal and tanzanite are also among the rare gems.
Who should wear alexandrite?
Alexandrite is the birthstone for June, so it is a lovely choice for anyone born that month. Beyond that, anyone who loves its colour change can wear it.
Gemstone traditions are cultural beliefs, not medical advice. See our gemstone and healing disclaimer.