Opal, Tourmaline and Pearls: A Gemologist's Guide to October's Birthstones
Share
If you were born in October, you got two birthstones, and they could hardly be more different. One flashes colors like a small storm. The other comes in nearly every color you can name. I love both, and I will tell you why, and how to wear them well.
OPAL: THE TRADITIONAL STONE
Opal is the traditional October birthstone. Its name is believed to come from the Sanskrit word upala. What makes opal special is play-of-color. As you tilt the stone, patches of color move and shift across the surface. It never looks quite the same twice.
Opal is also delicate. According to GIA, it ranks about 5 to 6.5 on the Mohs scale. That is softer than many gems, so store it apart from harder stones that could scratch it. I keep mine wrapped separately.
Care matters here. Warm soapy water is the safest way to clean opal. Avoid high heat and sudden temperature changes, because opal can fracture. If your piece is a doublet or triplet, which means layers joined with glue, prolonged contact with water can weaken that glue. So no long soaks.
Where does opal come from? Australia is the most productive source. Ethiopia, Mexico and Brazil also produce it. Fire opal from Querétaro in Mexico is a favorite of mine, with its warm, glowing orange.
If you are curious about how opal looks as a statement piece, I wrote about it in Opal Choker Necklaces.
TOURMALINE: THE NEWER STONE
Tourmaline was added to the October list more recently, and it makes a lot of sense. The name comes from the Sinhalese word toramalli, which means "stone with mixed colors." That is accurate. You can find pink, green, blue, and more.
A few varieties to know. Rubellite is the rich pink to red. Chrome tourmaline is a deep green. Paraiba-type tourmaline gets its color from trace copper, and it is priced well above other tourmalines. Brazil is its most common source.
For tourmaline jewelry, the practical news is good. It is generally harder than opal, rated about 7 to 7.5 on Mohs, though I would still treat it with some respect.
The AGTA has an October 2026 feature on both stones, if you want to read more.
WHERE PEARLS FIT IN:
Let me be clear: pearls are the June birthstone, not October's. But I find myself pairing them with October stones constantly, and not just for people born in June.
Here is why it works. A pearl has a soft, quiet glow. Opal has movement. Tourmaline has saturation. Put a baroque pearl next to a pink tourmaline, and the pearl calms the color down and lets it breathe. Put an opal beside a cream or white pearl, and the opal's flashes of blue and green look more like they belong there.
Opal and pearl jewelry also has something practical in common. Both are soft, so both need gentle care. They suit someone who treats her jewelry as something to be worn with attention, not something thrown in a bag. If you wear a pearl and gemstone necklace, put it on after your perfume and take it off before bed. It is the same habit for both.
HOW I DESIGN WITH THEM
When I make a piece with these stones, I think about how it will be worn. An opal in a ring will get knocked more than an opal in a pendant, so I usually suggest the pendant or earrings. Tourmaline is more forgiving, so a ring is reasonable.
For metals, I choose oxidized silver when I want a deeper, more weathered look, gold-filled for everyday warmth, and 18k solid gold when someone wants a lasting heirloom. I am still deciding which looks best with a particular opal each time, because every stone is different.
If you want to wear a longer necklace with pearls and a stone, my post How to Layer Pearl Necklaces will help you see how the lengths can work together.
A NOTE ON ANNIVERSARIES
Gift-givers might like this: according to GIA, tourmaline is the stone for an eighth anniversary, and opal is for the fourteenth. If you are marking one of those years, either stone can say so quietly.
"I hold an opal under a lamp, turn it slowly, and wait for it to show me where the color lives. Then I decide how to set it. You cannot rush that. The stone tells you what it needs." Claudine
A SOFT INVITATION
If you are an October baby, or you are shopping for one, write to me. I can talk through what suits the person: opal or tourmaline, pearl alongside or on its own, and which metal. Everything is made by hand in my home studio in Canada, and personalizing a piece is part of how I work.
Thank you for spending a few minutes with me.
Claudine
SOURCES
GIA, October Birthstones: https://www.gia.edu/birthstone
AGTA, October 2026 Birthstones: Opal and Tourmaline: https://agta.org/october-2026-