The September Birthstone: A Look Inside the Legend of Sapphire

If you were born in September, your birthstone comes with one of the richest backstories in the gem world. Sapphire has been worn by kings, prized by priests, and woven into legends about the sky itself — long before it became the classic anniversary and engagement stone we know today.

Here's a look at where sapphire's mystique comes from, the powers people once believed it held, and a few famous names who've made it iconic.

Where the Name Comes From

The word "sapphire" traces back to the Greek sappheiros, meaning "blue stone." While sapphire is best known for its deep blue color, it's actually a variety of the mineral corundum, and occurs naturally in nearly every color except red (which is corundum's other famous form — ruby).

The 423 carat cushion cut Logan Sapphire is one of the largest faceted blue sapphires in the world. This sapphire hails from Sri Lanka (formerly known as Ceylon)

Ancient Beliefs: Sky, Truth, and Protection

Long before sapphire was a birthstone, it was considered a direct link to the heavens.

• The sky itself. Ancient Persians believed the Earth rested on a giant sapphire, and that its reflection was what gave the sky its blue color. They called it the "Celestial Gemstone."
• A god's favorite stone. In ancient Greece, sapphire was associated with Apollo and worn by those seeking guidance from the Oracle at Delphi — people believed it opened a line to prophecy and the future.
• Royal armor against harm. Greek and Roman rulers believed sapphire protected its wearer from envy and danger, which helped cement its long association with crowns, royal jewelry, and power.
• A test of loyalty. One of the more colorful legends held that a sapphire would change color or lose its shine if the wearer's partner was unfaithful — making it an early (if unreliable) lie detector for love.
• Health and healing. Sapphires were also thought to carry medicinal powers, particularly for eye ailments and as protection against poison.

By the Middle Ages, the meaning shifted toward the sacred. Clergy wore sapphires to symbolize heaven and purity, and kings incorporated them into crowns and regalia as a mark of divine favor. Across nearly every era, the throughline stayed the same: sapphire meant truth, wisdom, loyalty, and protection.

A Modern Royal Romance

No modern sapphire story is more famous than Princess Diana's engagement ring. In 1981, Prince Charles gave her a 12-carat oval blue sapphire surrounded by a halo of diamonds — a striking departure from tradition at the time, since royal engagement rings weren't typically sold "off the shelf." The ring became instantly iconic.

Decades later, Prince William gave that same ring to Kate Middleton when they became engaged, turning it into one of the most photographed and recognized pieces of jewelry in the world. It's a rare case of a single ring carrying two generations of royal history — and it single-handedly renewed the public's love for sapphire engagement rings.

Why It's Still a Favorite Today

Beyond the folklore, sapphire earns its reputation the practical way too — it sits at a 9 on the Mohs hardness scale, just below diamond, which makes it an excellent choice for daily-wear rings that need to hold up over a lifetime. Combine that durability with centuries of symbolism around truth, loyalty, and protection, and it's easy to see why sapphire remains one of the most meaningful stones you can give — or wear yourself.

Whether you were born in September or you're just drawn to that unmistakable blue, sapphire carries a story that very few gemstones can match.

Interested in seeing sapphires in person? Stop by Gemma's Jewelers — we'd love to help you find the piece that's right for you.