August Birthstone Guide: Peridot and Spinel Jewelry (2026)

Why August Has Three Birthstones

Most months claim a single birthstone. August has three, and each earned its place at a different point in history. Sardonyx, a banded variety of onyx, is the ancient original: Roman soldiers carried sardonyx talismans engraved with Mars, the god of war, believing the stone brought courage in battle. Peridot became the modern August stone when the American National Association of Jewelers standardized the birthstone list in 1912. Spinel is the newcomer: in 2016, the Jewelers of America and the American Gem Trade Association added it as a third option, a long-overdue recognition for a gem that had spent centuries being mistaken for ruby.

For anyone born in August, this is good news. Three stones means three very different personalities to choose from: the sunny green of peridot, the rainbow range of spinel, or the earthy bands of sardonyx.

Key Takeaways

• Three stones, one month: August is one of only three months with three birthstones: peridot (modern), spinel (added in 2016), and sardonyx (traditional).
• Peridot is born of fire: it forms deep in the Earth's mantle and reaches the surface through volcanoes; a few crystals even arrive inside meteorites.
• Spinel is the great impostor: its red and pink varieties were mistaken for rubies for centuries, including in royal crowns.
• Durability differs: peridot measures 6.5-7 on the Mohs scale and spinel measures 8, so spinel is the better choice for rings worn daily.
• Sapphire covers the same palette: yellow and pink sapphires (Mohs 9) offer August's colors with heirloom-grade durability.

Peridot: The Gem Born of Fire

Peridot is one of the few gemstones that comes in only one color: green. The shade shifts from yellowish-green to olive depending on how much iron the crystal contains, but that signature spring-green glow is unmistakable. Ancient Egyptians mined peridot on the island of Zabargad in the Red Sea more than 3,500 years ago and called it the "gem of the sun." Some historians believe Cleopatra's famous emerald collection was actually peridot.

What makes peridot unusual is where it forms. Most gemstones crystallize in the Earth's crust; peridot forms far deeper, in the mantle, and reaches the surface through volcanoes. A small number of peridot crystals have even been recovered from pallasite meteorites, making it the only birthstone that sometimes falls from the sky.

On the practical side, peridot measures 6.5 to 7 on the Mohs hardness scale. That is durable enough for earrings, pendants, and occasional-wear rings, but it does ask for some care: avoid rough daily wear, remove peridot rings before workouts or housework, and clean the stone with warm soapy water rather than ultrasonic cleaners.

Spinel: The Great Impostor

If peridot is a specialist, spinel is a shapeshifter. It appears in red, pink, cobalt blue, lavender, orange, and nearly every shade between. For most of history, nobody knew: red spinel is so close to ruby in color that some of the most celebrated "rubies" in the world, including the Black Prince's Ruby set in the British Imperial State Crown, are actually spinels. It was not until the late eighteenth century that gemologists could reliably tell them apart.

That long case of mistaken identity is exactly why collectors love spinel today. It offers ruby-like reds and sapphire-like blues, almost always untreated, which is increasingly rare in colored gemstones. And with a Mohs hardness of 8, spinel is comfortably durable for everyday rings.

At Edward's, our gem desk focuses on the classic trio of sapphires, rubies, and emeralds, and we regularly source fine spinel and other colored stones for custom projects. If a cobalt spinel or a vivid pink stone is on your list, our GIA-graduate jewelers can bring options to the table and walk you through them side by side.

Sardonyx: The Ancient Original

Sardonyx deserves more attention than it gets. This banded stone layers reddish-brown sard and white onyx into natural stripes, and it has been carved into cameos and signet rings for more than 4,000 years. It is more affordable than peridot or spinel, making it a lovely choice for a first birthstone gift, and its warm, earthy look pairs beautifully with the yellow gold that dominates 2026 jewelry trends. Read more about yellow gold's comeback.

August Colors, Heirloom Durability: Sapphire Alternatives

Here is an honest piece of jeweler's advice: if you are choosing an August birthstone piece that will be worn every single day for decades, hardness matters. Peridot at 6.5-7 will slowly pick up scratches on a daily-wear ring. This is where sapphire, our house specialty, earns a mention. Sapphire measures 9 on the Mohs scale, harder than any August stone, and it happens to cover the entire August palette.

If you love peridot's golden-green warmth, a yellow sapphire delivers a similar sunlit color with everyday durability. This cushion-cut yellow sapphire ring shows exactly what we mean:

If pink spinel is what draws you, a pink sapphire carries the same blush tones:

And if cobalt-blue spinel is the dream, classic blue sapphire is its closest heirloom cousin.

You can explore the full range in our sapphire collection, or read our sapphire buying guide for a deeper dive into color and origin.

How to Choose an August Birthstone Gift

• For daily-wear rings: choose spinel (Mohs 8) or a sapphire alternative (Mohs 9) over peridot. Save peridot for earrings and pendants where it is protected.
• For color: peridot looks best in yellow gold, which deepens its warmth. Spinel and sapphire suit both white and yellow metals; see our guide to choosing between white and yellow gold.
• For treatments: ask. Most spinel is untreated, which is part of its value story. Reputable jewelers disclose any treatment on any colored stone; it affects both price and care.
• For meaning: peridot is the traditional 16th wedding anniversary gem, so an August birthstone can do double duty as an anniversary gift; see our anniversary jewelry by year guide.

FAQs

What is the August birthstone?

August has three birthstones: peridot (the modern stone), spinel (added in 2016), and sardonyx (the traditional stone). Peridot, with its yellow-green color, is the most widely recognized.

Is spinel a real birthstone?

Yes. Spinel was officially added as an August birthstone in 2016 by the Jewelers of America and the American Gem Trade Association, joining peridot and sardonyx.

Is peridot durable enough for an engagement ring?

Peridot measures 6.5-7 on the Mohs scale, so it can scratch with daily wear. For an everyday ring in August colors, spinel (Mohs 8) or yellow sapphire (Mohs 9) are more durable choices.

What metal looks best with peridot?

Yellow gold is the classic pairing; it deepens peridot's warm green. White metals give it a cooler, more modern look.

Visit Us in San Francisco

Photographs flatten colored gemstones. Peridot's glow, spinel's fire, and sapphire's depth only reveal themselves in person, under real light, next to your skin tone. Our family has been helping San Franciscans match stones to stories since 1983, in the same showroom at 888 Brannan Street where parents who bought engagement rings from Edward now send their sons and daughters. Bring your questions, your budget, and your August birthday, and we will put real stones on the counter. In-stock pieces under $10,000 ship free within the US, and every purchase includes 10-day returns and exchanges.