October's Birthstones: Opal and Tourmaline

October is the month of falling leaves and cosy, darker evenings. It's shared by fair-minded Libra and passionate Scorpio, and it's lucky enough to have two birthstones: opal and tourmaline.

What is the October birthstone?

October birthdays can choose between colour-shifting opal and multicoloured tourmaline. They're very different stones, but both hold a kaleidoscope of colour.

What is opal?

Opal has an iridescence like nothing else. Tilt it in the light and flashes of colour dance across its surface, which is why the Romans prized it above every other gem.

There are two types. Precious opal shows that famous "play-of-colour"; common opal doesn't. Because opal holds water, typically between 3% and 21%, it's classed as a mineraloid rather than a mineral.

Opal forms when rain soaks into ancient rock in dry landscapes such as the Australian outback, carrying dissolved silica with it. As the water evaporates, the silica is left behind in the cracks and slowly becomes opal.

What does opal mean?

The name is thought to come from the Sanskrit upala, meaning jewel, and the later Greek opallios, meaning "to see a change in colour". Bedouin legend said opals held lightning and fell from the sky in thunderstorms, while the ancient Greeks believed they gave the gift of prophecy.

Today, opal is a symbol of hope, purity and truth. It's said to amplify thoughts and feelings, bringing them to the surface so they can be worked through, and to sharpen intuition. Until huge deposits were found in Australia in the 19th century, it was a stone prized by royalty.

Our solid gold Interstellar designs set opal alongside lab-grown diamonds. Try the Solid Gold Interstellar Opal and Diamond Drop Necklace, the Solid Gold Interstellar Opal and Lab Grown Diamond Cluster Necklace or the matching drop earrings.

Shop opal jewellery

What is tourmaline?

Tourmaline takes its name from the Sinhalese word turmali, meaning "stone with mixed colours". And it lives up to it: a single stone can shift from vivid pink through yellow to emerald green. Ancient mystics believed all that colour inspired artistic expression.

With such a range of shades, tourmaline was often mistaken for rubies and emeralds. Today, the most sought-after is the rare, neon blue-to-green Paraíba tourmaline.

It's clever, too. Tourmaline can generate an electric charge under pressure, which saw it used in pressure gauges for submarine sonar during the Second World War.

What does tourmaline mean?

Tourmaline is thought to soothe a broken heart, encouraging love and gently easing pain. Each shade carries its own meaning, and many people are drawn intuitively to the colour that speaks to them. Pink tourmaline is all about love and compassion.

Wear yours every day with the Gold October Pink Tourmaline Birthstone Pendant Necklace, or treasure it forever in the Solid Gold October Birthstone Pink Tourmaline Pendant Necklace.

Shop birthstone jewellery · Discover more in our gemstone guide