The birthstone for October is the opal gemstone, one of the world's most rare and admired gems. Its kaleidoscopic colors strike the perfect balance between fun and elegance, and no two gems are the same. If you’re as interested as I am in adding some opal jewelry to your collection, keep reading for everything you need to know to make the most of them!

October’s opal sits on the Mohs Hardness Scale at 5.5-6.5. It’s not just a sparkle, but it’s a lot of different forms. 

Below are a couple of examples:

Found in Peru and Mexico, this is far and away my favorite kind of opal. If you’ve read many of my other blog posts, it’s abundantly clear that I love anything and everything pink. 

Another benefit of this type of opal is that it is slightly more durable than the typical blue variety. Pink opal has traces of another stone called chalcedony, giving it a hardness of 5-6. 

I love that black opal sounds so shadowy and mysterious. And it is appropriate, given that it is the most rare kind of opal, found solely in Australia. 

Black opal is an extremely sought-after gem because it is so rare, and the darker base color of this opal makes the rainbow patches of color shine even more vibrantly. It is something else to look at.

The October birthstone is one of the more delicate gemstones; as such, you need to take regular care of it if you want it to last (more details to come later). But if you clean opal periodically and leave it in the jewelry box during messier or more movement-intensive activities, it can last for decades. 

Speaking of jewelry boxes, you’ll want to store your opal jewelry in a cloth bag with padding inside. If you’re putting it away for a particularly long time, such as weeks or months, it’s smart to wrap the gem in a bit of wool or cotton cloth dampened with a few drops of water. This peculiar-sounding trick will keep the opal from overdrying and cracking.

When it comes to opal, no other country can take the crown from Australia, which produces 95% of the world’s opal gemstones. However, there’s a fascinating variety of different places across the globe that contribute to that other 5%:

• Brazil
• Canada
• Czech Republic
• Ethiopia
• Honduras
• Hungary
• Indonesia
• Mexico
• Nevada, USA
• Nicaragua

Deposits of opal even exist on Mars. Yes, you read that right - the planet. 

Some people may try to tell you that wearing or carrying opal will bring you bad luck. What you don’t hear as often about is that, through most of history, opal was a good luck charm and is still associated with many positive outcomes.

In medieval times opal supposedly repaired eyesight. Today, the October birthstone symbolizes passionate love, purity, hope, and truth. With its whimsical, otherworldly, and joyful rainbow glint, it’s easy to see why. 

• The October birthstone is formed from silica, the same material as glass, and takes about 5 million years to solidify into just one centimeter of opal.
• Opal’s play-of-color is due to millions of tiny silica spheres refracting light. Boulder opals can display all seven colors of the rainbow.
• The name "opal" is believed to come from the Latin word 'opalus' meaning "precious stone," although some references suggest it originated from the Sanskrit word 'upala' meaning "jewel."
• Opal artifacts date back to 4,000 BC, and in the Middle Ages, opal was considered a lucky stone believed to possess the virtues of all other gemstones.
• Opal's reputation suffered after Sir Walter Scott's novel, Anne of Geierstein, portrayed the stone as bringing bad luck and tragedy to its wearer, causing a decline in opal sales.
• Two famous opals, Olympic Australis and The Virgin Rainbow, are worth millions of dollars and are highly prized for their size, rarity, and unique qualities.

Between world history and recent pop culture history, some fascinating examples of iconic figures show their love for the October birthstone.

According to legend, the Roman senator Nonius owned a huge and brilliant opal. Roman General Mark Antony was obsessed with buying it from him so he could gift it to his lover, Cleopatra, but Nonius refused to part with it, even to the point of banishment. These two took “gemstone enthusiasts” to a whole new level! 

Shifting forward, one of Nicole Kidman’s most famous early red-carpet moments involved opals—lots of them. For the 1996 Oscars, New York jewelry store Fred Leighton loaned her a stunning multi-strand Victorian opal necklace in enchanting white, pink and blue pastel hues.

Remember that the October birthstone is a gem of delicate sensibilities if you remember nothing else from this blog. Even household dust has a greater hardness level than opal at 7-7.5. So, if you want to keep these breathtaking gems looking their best, there are several steps you should take.

First, know if your accessory is solid opal, a doublet or triplet. A doublet consists of a layer of opal glued over a layer of darker material, such as black glass or plastic, making the play-of-color in a light-colored opal easier to see. A triplet is very similar, except on top of the opal layer is a protective third layer of quartz, glass or plastic. 

If your opal piece is a doublet or triplet, do not submerge it underwater to clean it. Submerging an opal damages the glue that joins the layers and causes them to separate. Instead, dampen a soft cloth with mild dish soap and water and gently wipe the stone. 

Consider making opulent opal jewelry a great addition to your treasure collection. Jedora offers amazing opal rings, necklaces, earrings, bracelets, pendants and opal gemstones!

October has two birthstones because the original opal became the more durable tourmaline.

The October birthstone, opal, can have a base color of blue, pink, black or white, and all types display the rainbow sparkle phenomenon called play-of-color.

Play-of-color is the official name for opal’s multicolor sparkle, caused by the interaction of light with the stacks of silica molecules inside the gem. 

Opal is more expensive than tourmaline.

Documentation of opal exists even before the first century AD, but many consider the official “discovery” to have been in 1939 in Kenya, Africa, during an archaeological expedition.

Some people associate wearing opal with magnified spiritual energy and clarity, increased creativity, and emotional healing.

• Fremantle Opals - Opal Legends
• Opals Down Under - Doublets and Triplets Explained

Bethany Milsom contributed to this article.

Edited by Missy Johnston.