October Birthstones: Opal and Tourmaline
October birthdays are lucky: they get not one but two of the most colourful stones in the mineral world. Opal is October's traditional birthstone, and tourmaline (especially pink tourmaline) is its much-loved modern partner. Here's our friendly guide to both — what they actually are, how to spot a look-alike, and how to keep them looking their best.
October's birthstones at a glance
Opal: milky white, pink, blue-green, fiery orange and rainbow-flashed · 5.5–6.5 on the Mohs scale · Ethiopia, Mexico, Peru and Australia · handle gently, keep away from heat
Tourmaline: pink, red, green, blue, black and 'watermelon' · 7–7.5 on the Mohs scale · Brazil, Madagascar, Afghanistan and more · tougher, easy to care for
Why does October have two birthstones?
Birthstone lists have been drawn up and revised by jewellers over the last hundred years or so, and October has ended up with a choice. Opal has been linked with October for generations, and tourmaline sits alongside it on the modern lists.
So if you're born in October, you can pick whichever speaks to you — or, like plenty of our customers, have one of each.
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Opal: the stone with a rainbow inside
Opal is a little different from most crystals. It's made of silica, the same ingredient as quartz, but it isn't crystalline. Instead it's built from millions of tiny silica spheres packed together, with water held in the spaces between them — anything from a few per cent to around a fifth of an opal can be water.
When those spheres are the right size and neatly stacked, they split light into flashes of colour. That shimmer is called play of colour, and it's what most people picture when they think of opal. Opal without it is called common opal — and it can be every bit as beautiful.
These are the opals you'll usually find in our shop:
Ethiopian opal — mined in Ethiopia's Wollo region, often with bright play of colour against a pale, glowing body.
Mexican fire opal — warm orange to red body colour, sometimes with flashes of play of colour too.
Peruvian opal — a soft sea-blue to green common opal from the Andes in Peru, gentle and milky rather than flashy.
Pink opal — a sugary-pink common opal, also usually from Peru, lovely as raw pieces and polished slices.
Black opal — opal with a dark body colour that makes its flashes of colour really glow, most famously from Lightning Ridge in Australia. Ours are loose, polished cabochons: just the stone itself, ready to treasure or have set.
Opal jewellery from our cabinets — tap any photo to see the piece:
Ethiopian Opal Sterling Silver Ring (Q/8) 
Mexican Fire Opal Sterling Silver Ring (O/7) 
Pink Opal 925 Sterling Silver Pendant 
Mexican Fire Opal Sterling Silver Pendant 
Statement Opal and Marcasite Sterling Silver Ring 
Emerald, Ethiopian Opal, Sapphire and Ruby Sterling Silver Necklace
In crystal lore, opal is traditionally associated with creativity, inspiration and self-expression.
Did you know? In the 1800s opal briefly picked up an 'unlucky' reputation, often blamed on Sir Walter Scott's 1829 novel Anne of Geierstein. Queen Victoria, a great opal fan, is said to have helped restore its good name by giving opal jewellery to her family.
If you'd rather have opal as a stone than as jewellery, our raw pink opal pieces, polished slices and loose black opal cabochons are lovely to hold and display:
Pink Opal Unpolished Specimen 
Pink Opal Unpolished Specimen 
Pink Opal Polished Slice 
Black Opal Cabochon Cut Gemstone
Opal or opalite? A quick honesty check
This is one we're asked about a lot. Opalite is a pretty, milky glass that glows blue against a dark background and orange against a light one — but it's man-made glass, not natural opal. We stock it and we love it, but we always label it clearly as opalite so you know exactly what you're getting.
If you see a very cheap 'opal' with a perfectly even, uniform glow, it's always worth asking what it really is. Real opal has natural variation — no two pieces are quite the same.
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Tourmaline: a whole rainbow in one family
Tourmaline isn't a single mineral but a family of boron silicate minerals, and it comes in more colours than almost any other gemstone — pink, red, green, blue, yellow, black and just about everything in between. For October, pink tourmaline is the favourite.
Our personal favourite is watermelon tourmaline: a pink centre wrapped in a green rim, just like a slice of watermelon. It forms when the chemistry around a growing crystal changes partway through, so the crystal records its own story in colour.
Did you know? Tourmaline is pyroelectric and piezoelectric, which means a crystal can build up a small electrical charge when it's warmed or squeezed. Dutch traders in the 1700s reportedly used warmed tourmaline to pick ash out of their pipes. The name comes from the Sinhalese word 'turmali', from Sri Lanka.
In crystal lore, pink tourmaline is traditionally associated with love, kindness and compassion, and it's often paired with the heart chakra. Its darker cousin, black tourmaline, is traditionally seen as a stone of protection.
Tourmaline jewellery and pieces from the shop:
Pink Tourmaline Sterling Silver Ring (O/7) 
Watermelon Tourmaline Sterling Silver Ring (O/7) 
Watermelon Tourmaline Tree of Life Pendant 
Pink Tourmaline and Fluorite Sterling Silver Bracelet 
Pink and Blue Tourmaline Specimen 
Natural Pink and Green Tourmaline Rods
One honest note: some pink and red gem tourmaline on the market is heat-treated or irradiated to deepen its colour. It's a long-established, stable practice in the gem trade, but if natural colour matters to you, just ask us about a particular piece — we'll tell you what we know. (We've written more about treated colour in our guide How to Tell If Citrine Is Real or Heat-Treated.)
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How to look after opal and tourmaline
These two need quite different care, so it's worth knowing which is which.
Opal (handle gently):
Wipe with a soft, slightly damp cloth rather than soaking it.
Ethiopian opal is 'hydrophane', meaning it can soak up water and turn cloudy for a while. It usually clears as it dries slowly, but keep it away from oils and lotions, which can change it for good.
Keep opal away from heat, hot sunny windowsills and sudden temperature changes, which can cause fine cracks known as crazing.
No salt, harsh chemicals or ultrasonic cleaners. Opal is fairly soft, so store it apart from harder stones like quartz.
Tourmaline (a bit tougher):
Polished tourmaline jewellery and tumble stones can be washed in lukewarm soapy water with a soft brush, then dried well.
For clusters and pieces still in quartz or rock, a soft dry brush or a gentle rinse is best — don't leave them soaking.
Avoid high heat and ultrasonic cleaners.
If you like to cleanse your crystals energetically, gentle methods such as smoke, sound or moonlight suit both stones — just skip salt and water soaks for opal. Our older posts What crystals can I put in water? and Cleansing & Charging Your Crystals have more ideas.
Gift ideas for October birthdays
A little something: a watermelon tourmaline bracelet or pendant, a raw pink opal piece or a natural tourmaline rod.
A birthday to remember: an opal or tourmaline ring or pendant — our sterling silver pieces are mostly one-offs, so each one really is unique.
For the crystal lover who has everything: a tourmaline cluster or a polished pink opal slice for their shelf.
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Shop October birthstones
Opal
Tourmaline
Stock changes quickly and many of these are one-of-a-kind, so if something has found a new home, ask us — we often have more in the shop than online.
Choosing a present for an October birthday? Pop into the shop at 61 South Street, St Andrews, or send us a message — we'd love to help you find the perfect opal or tourmaline.
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