The birthstones for October are opal and tourmaline. Yes, October has two birthstones, offering a broad range of choices to mark this special month. If you are celebrating an October birthday or even an October milestone, you have a unique opportunity to choose jewelry that aligns with your style, as there are so many intriguing options available in both opal and tourmaline.
Why October has two birthstones
Opal has long been the traditional October birthstone, celebrated for its iridescent beauty. The American National Retail Jeweler’s Association created the standard list of birthstones, one for each month, in 1912. Forty years later, the group, which is now known as Jewelers of America, broadened the list to include tourmaline for October.
The addition of tourmaline as a birthstone gives October babies the chance to choose a gem with a different hardness level and color profile. Many find this useful because, as beautiful as opal is as a gemstone in jewelry, it’s relatively soft. Tourmaline gives jewelry wearers another option to celebrate October but with a more durable gem. Tourmaline also expands the color ranges available for this month’s birthstone.
The Opal birthstone
Opal has been loved for thousands of years, often thought to bring luck to its wearer. It has been found in locations as varied as Ethiopia and Australia, where it has been mined for decades.
Formation & Composition
The traditional October birthstone, opal, is an amorphous gemstone, meaning it’s not crystalline in structure. This makes it a mineraloid, rather than a true mineral. It is composed of silicon dioxide and water. The structure of opal, which contains tiny silica spheres, allows for the beautiful, iridescent play of light that this gemstone is known for. No two opals are alike. Common opal does not display this play of light but occurs in a variety of colors that includes a range of pastels.
Opals can commonly be seen as milky or pearly in color, displaying rainbow colors. But there are also many other varieties of opal:
- Boulder opal has fragments of the host rock, called matrix, attached
- Harlequin opal displays square blocks of colors
- Fire opal exhibits warm colors reminiscent of flames: red, orange, or yellow
- Black opal has a dark body color
In addition to its many varieties, there are also synthetic opals that are just as stunning.
Opals are available in a range of colors including black, red, orange, yellow, brown, gray, cream, pink, and white.
As a softer gem, opals are perfect in settings where they will be somewhat protected from nicks and scratches, such as necklaces. October birthstone rings are absolutely gorgeous in opal, as long as the wearer takes proper care of them.
The Tourmaline birthstone
Tourmalines are a more recent discovery compared to opals, so their history isn’t quite as rich. However, tourmalines were discovered more than 500 years ago, possibly for the first time by a Spanish explorer in Brazil. Their beauty has caused them to be confused for emeralds and rubies more than once!
Tourmaline is the modern October birthstone, added to the list in 1952. This gemstone is a mineral that is available in many different colors, each depending on the chemical makeup of the gem. It’s formed of crystalline boron and silica in combination with iron, magnesium, potassium, and other elements.
There are many types of tourmaline:
- Schorl is dark or black
- Dravite ranges from yellow to black
- Elbaite may be red, blue, green, or colorless
Schorl is the most common species of tourmaline. Other types include Paraíba tourmaline, from the Paraíba region in Brazil, indicolite, which is a deep blue, and rubellite, which is a deep red. There is even a cat’s-eye tourmaline.
One interesting feature of many tourmaline gems is that they are magnetic. When warmed, they may electrically attract bits of paper, dust, or ash.
There are almost as many colors of tourmaline as there are in a rainbow: red, pink, yellow, green, blue, and even black. There are multi-color variations, too—even the suitably-named watermelon tourmaline that is ringed in green which fades to white before switching to pink.
With a 7–7.5 rating on the Mohs Hardness Scale, tourmalines are a durable birthstone selection for October. Tourmaline would be quite appropriate for a birthstone ring, as well as a necklace, brooch, or earrings.
October birthstones: a multitude of options
As you can see, those lucky enough to be born in October have a wealth of choices when it comes to choosing birthstone jewelry. With gorgeous gems that range almost the entire rainbow, October birthstones present nearly infinite possibilities in terms of cut, color, setting, and design. Take advantage of both modern and traditional October birthstones choices to expand your selection and find the perfect piece to commemorate this wonderful month. Find an American Gem Society jeweler near you!