October Stones - Opal and Tourmaline | Stewart Kuper Jewelers

October Stones – Opal and Tourmaline

October 18, 2019
Helix House

Welcome back to the Stewart Kuper Jewelers blog! We have talked before about the traditions of birthstones but we never wrote about October’s stones! Two stones are traditionally associated with October births, opal and tourmaline but it hasn’t always been this way! We’ll talk about that and more this time on the blog.


Briefly, before we get into the specifics of opal and tourmaline, it’s worth mentioning the tradition of birthstones. The main idea, is associating gemstones with months or dates, which make for great traditional gifts.

The western custom of it has religious origins, with some historians believing there to be a connection between the twelve months, signs of the zodiac, and twelve different stones seen on the breastplate of the High Priest of the Israelites in the Book of Exodus. Another theory holds that in the eighth and ninth century there were religious works associating different stones with apostles and virtues.

Eastern tradition meanwhile has birthstones that are less tied to the date but rather astronomical events or sights, positions of planets and constellations. 

Now, those are the origins, but the stones have not stayed static throughout the years. As styles and tastes have changed, so too have the stones associated with the different birth months.

As of 1912, the traditional birthstones of October in the U.S. are opal and tourmaline (the Brits just use opal).

Opal shining


Opals are an iridescent gem, with many different colors in a great kaleidoscopic shimmer. There’s even a word for it: opalescence. Looking at it microscopically reveals how it works. Opals are made up of grids of silica spheres (tiny quartz) packed in tightly that create these facets for the light to bounce off and shine. They are simply gorgeous stones. 

Opal possibly derived from the Latin opalus or possibly the Sanskrit úpala, whichever the case, opal has a long history as a gem of importance. At one point in time, opal was valued higher than all other gems by the Romans. People in the Middle Ages believed opals to be stones of good fortune as the opal shined with light and color of all other gems, thus having all the virtues (as mentioned earlier).

Opal has a hardness of 5 – 6.5 on the Mohs scale, so you want to be sure to store any opal pieces separate to prevent harder gems like diamonds or rubies from scratching it. Sudden temperature changes or high heat can cause opals to fracture, so leaving an opal ring in the car on a summer day is a bad idea.

Tourmaline, red, green, mixed


Tourmaline is an interesting stone, it has a range of colors (in fact it’s name means ‘stone with mixed colors’) that can sometimes cause confusion on what it actually is. A red gem in Russia’s crown jewels called the Caesar’s Ruby pendant is in fact a red tourmaline!

Tourmaline is predominantly found in Brazil, but there are other mines in the Middle East and Africa. Here in America they have been produced in California and Maine. It doesn’t have quite the long history of its other October birthstone brother, but has had an interesting one regardless. For example, in the 19th century, chemists used tourmaline to polarize light.

As mentioned, tourmaline has a number of possible colors, including blue, green, yellow, pink, and sometimes it is even colorless. You can find the perfect tourmaline gift in the color your loved one is sure to love!

Tourmaline is a great gem for everyday wear for a number of reasons. At a 7 – 7.5 on the Mohs scale, the colorful stones are strong enough to endure most chemicals and lights, though heat can still be damaging.

This has been a brief rundown on the two birthstones of October, opal and tourmaline. While they might not be at the forefront of most people’s minds, a stone that is tied to them personally, representing their birth can be a treasured gift. Looking to find out more? Give us a call and schedule your appointment today! We’d be happy to help you find the perfect gift.