Twelfth Anniversary Stone: Alexandrite
The twelfth wedding anniversary stone is alexandrite, a rare colour-change gem. Here's what it is, how it holds up to everyday wear, and how to turn it into a piece worth keeping.
Key takeaways
- The traditional 12th anniversary stone is alexandrite, the colour-change gem, while some modern lists use opal instead.
- Alexandrite is genuinely rare and famously changes colour, looking green in daylight and red or purple under lamplight.
- It is hard and durable, sitting at 8.5 on the Mohs scale, which makes it well suited to a ring you wear every day.
- Because natural alexandrite is so scarce and costly, most affordable pieces use lab-grown alexandrite, which shows the same colour change.
- Alexandrite is also a birthstone for June, alongside pearl and moonstone, so a 12th-anniversary June couple gets a nice overlap.
- Vanhess sources and sets alexandrite by hand in our Coquitlam workshop and will be straight with you about natural versus lab-grown.
What is the 12th anniversary stone?
The 12th anniversary stone is alexandrite. That is the traditional gift, and it is the more interesting of the two options by a distance. The lists do differ here: some modern anniversary guides put opal at year twelve instead, which is a softer, very different stone. So you have a genuine choice, and it is worth understanding both before you decide. Our anniversary stones guide sets year twelve in the context of the full run of years if you want the bigger picture.
What alexandrite actually is
Alexandrite is a variety of the mineral chrysoberyl, and it does something almost no other gem does: it changes colour depending on the light. In daylight or under blue-white LED it reads green to bluish-green. Under a warm incandescent bulb or candlelight it shifts to red, purple, or raspberry. People sometimes call it "emerald by day, ruby by night," which overstates it a bit, but the effect is real and it is caused by trace chromium in the crystal reacting to different wavelengths of light. The stone was first found in Russia's Ural Mountains in the 1800s and named after the young Tsar Alexander. On durability it scores well. Alexandrite sits at 8.5 on the Mohs scale, harder than most everyday gems and well above the point where daily wear becomes a worry. For a stone you can put in a ring and forget about, that hardness is a real advantage.
Why alexandrite for year twelve
Alexandrite's whole identity is change. A stone that quietly becomes something else as the light shifts is a fitting emblem for a marriage twelve years in, one that has already moved through several versions of itself and kept going. That is the honest reading, and it holds up without any need to dress it in mysticism. There is also a plain practical reason the stone carries weight: it is rare. Fine natural alexandrite is one of the scarcer gems on earth, which has always given it a certain prestige. If you were born in or married in June, there is a bonus, since alexandrite shares that month as a birthstone. You can see how it sits alongside its neighbours in our June birthstone page.
Choosing a piece for your 12th
The first honest conversation to have is natural versus lab-grown. Natural alexandrite with a strong colour change is spectacularly expensive and often only found in small sizes. Lab-grown alexandrite is real chrysoberyl made in controlled conditions; it shows the same colour shift, and it costs a fraction of the natural stone. Neither is a con. We will tell you which you are looking at and price it accordingly, and for most twelfth-anniversary budgets, lab-grown is the sensible way to get a stone with a genuine, visible colour change. Because the hardness is high, alexandrite is one of the few anniversary stones we are happy to put in an everyday ring without hesitation. A prong setting shows off the colour change from the side, where the shift is easiest to see, though a bezel is fine too if the wearer is hard on their hands. It also works beautifully in a pendant or drop earrings, where it catches changing light through the day. We design and set alexandrite by hand here in Coquitlam, and you can begin a one-off piece through our bespoke anniversary service. If you would rather go with the modern option, opal is a lovely, colourful stone, but be aware it is soft and needs the careful handling described below.
If you choose opal instead
Opal, the modern year-twelve pick, is a very different animal from alexandrite. It is prized for its play-of-colour, the flashes of blue, green and orange that seem to float inside the stone, but it is soft and water-sensitive. Opal contains water and can dry out and craze if it is kept somewhere hot or very dry, so it is best not left in a car or by a window. Keep it away from ultrasonic and steam cleaners entirely, clean it only with a soft damp cloth, and put it on after perfume and lotion rather than before. For an everyday ring, opal is a risky choice and much happier in a pendant or earrings. If you love the flashes of colour, our opal guide explains how to buy and care for one properly.
Turn your twelfth anniversary stone into a piece you’ll wear
Bring the year, the stone and a rough budget. Our on-site goldsmith in Coquitlam will design it with you — reset a stone you already own, or build something new around the right gem.
Prefer to talk? Call our studio at (604) 653-6449.Frequently asked questions
What is the 12th anniversary gemstone?
Alexandrite is the traditional 12th anniversary stone, known for changing colour between green in daylight and red or purple under lamplight. Some modern anniversary lists use opal instead, so both are considered appropriate.
Does alexandrite really change colour?
Yes. It genuinely shifts colour with the light source because of trace chromium in the crystal. In daylight it looks green to bluish-green, and under warm incandescent light it turns reddish or purple. The strength of the change varies from stone to stone.
Is alexandrite durable enough for an everyday ring?
Yes. It scores 8.5 on the Mohs hardness scale, harder than most everyday gems, so it stands up well to daily wear in a ring. It is one of the more practical anniversary stones for a ring you never take off.
Why is natural alexandrite so expensive?
Fine natural alexandrite with a strong colour change is one of the rarest gemstones in the world and is usually found only in small sizes. That scarcity drives the price. Lab-grown alexandrite offers the same colour change at a much lower cost.
Is lab-grown alexandrite a real gemstone?
Yes. Lab-grown alexandrite is genuine chrysoberyl created in controlled conditions rather than mined. It has the same makeup and shows the same colour change as natural stone. We will always tell you which one you are looking at and price it honestly.
Should I choose alexandrite or opal for a 12th anniversary?
If you want a durable stone for an everyday ring, alexandrite is the stronger choice at a Mohs 8.5. If you love shifting flashes of colour and will wear it in a pendant or earrings, opal is a beautiful option, but it is soft and needs gentler handling.
Is alexandrite connected to any birth month?
Yes. Alexandrite is one of the June birthstones, alongside pearl and moonstone. That makes it a nice fit for a June couple celebrating their twelfth anniversary.
Can Vanhess make a custom alexandrite piece?
Yes. We source and set alexandrite by hand in our Coquitlam workshop and can build a one-off ring, pendant, or pair of earrings through our bespoke anniversary service. We are happy to talk through natural versus lab-grown to match your budget.