If you have an August birthday, you have not one but three beautiful birthstones to honor you. While the peridot is featured in many of today’s most-stunning jewelry pieces, spinel can be equally fascinating. Sardonyx is the third birthstone, and it claims a more ancient history. Our August edition of the birthstone series looks at peridot, spinel, and sardonyx, what significance they hold, and how you can wear them in honor of your birth month or any month of the year.
Peridot, a gorgeous light green gemstone, is a type of olivine, a mineral made of magnesium iron silicate. While the most prized peridot gems are a vibrant light green — often called “grass green” — they can range from yellow green to brownish green, all depending on how much iron they contain. Peridot gems with a hint of yellow in the green are the most common. Because of the way it’s formed, peridot has a narrower range of colors than other minerals, but this also means that peridot is more celebrated for its unique traits.
Unlike many other gems, peridot forms in volcanic rocks in the Earth’s upper mantle. Most other gem-quality stones form closer to the Earth’s surface in the crust. Peridot often appears in basalt rock that’s been pushed to the surface by lava flows.
But the Earth isn’t the only place that you can find peridot — it can also come from outer space! The gemstone sometimes appears in pallasite meteorites that fall to earth, which are named for their intricate matrix design. In peridot meteorites, the gemstones are suspended around iron and nickel metals.
Peridot gemstones have a rating of 6.5 to 7 on the Mohs scale for hardness, and although they sometimes need more care to avoid scratching, they are rarely subjected to heat treatments to improve their color. Peridots have a naturally attractive sheen, double refraction, and can sometimes have small mineral deposits inside them, usually brown or black. Sometimes, they have disk-shaped inclusions called lily pads, which form in spots where other crystals once were.
Peridot's History and Symbolism
Peridots have been around for a long time. The earliest recorded source comes from ancient Egypt on a fog-covered island in the Red Sea. This island, Topazios, was later named Zabargad, and it was from here that the coveted light green gems began their move through ancient civilizations.
Because peridot symbolized light and the power of the sun, people cherished these gems as their protection against nightmares and evil spirits. Many people wore the gems on their clothing or tied around their arm to keep them safe while traveling. They also believed that the gems offered even more protection when they were set in gold.
Myanmar (formerly Burma) was another important mining site, especially in the Mogok Valley. Peridot from here was often a darker green and could be cut into large pieces. Today, you can find peridot mined in Myanmar, Pakistan, China, Norway, Hawaii, and Arizona. In fact, the San Carlos Apache Reservation in Arizona is the largest source of peridot in today’s market.
Spinel is another beautiful birthstone you might love to wear. This gem is most often red but can be orange, pink, blue, purple, or blue-black. As a mineral, it’s made of magnesium and aluminum combined with oxygen. It can also have trace amounts of iron, chromium, zinc, or manganese.
The color variability makes spinel an exceptional and easily-individualized gem. If you’re wearing bright red or vibrant pink spinel, your gem has more chromium. Orange and purple spinels have more iron mixed with chromium, and blue spinels have more iron. If you ever see a vibrant blue spinel, it’s an exceptionally rare stone that likely contains cobalt.
In terms of prestige, vibrant red and cobalt blue spinel gems are the most sought after, followed by vibrant pink or orange stones.
Spinel is harder than peridot, measuring an 8 on the Mohs scale. They’re not quite as durable as rubies, sapphires, or diamonds, but spinels are less likely to get scratches on the surface.
Spinel's History and Symbolism
Spinel’s have had a prominent place throughout history, even though people thought they were something else. For centuries, people thought rubies and red spinels were the same gem — and the same goes for sapphires and blue spinels. While these gems sometimes came from the same mine, they’re not the same mineral — rubies and sapphires are corundums made of aluminum oxide and trace minerals.
Afghanistan and Tajikistan were once the most important mining spots for spinels. The entire region was known as Balascia, where Balas rubies, the historical name for red spinel, came from. Spinels from this region were the largest and most sought-after. Myanmar and its Mogok Valley were also an important source for spinel. The gems here were smaller, but they had a natural sheen that locals called “spirit-polished.”
Today, you can find spinel mining in countries like Vietnam, Russia, Cambodia, and Australia.
Sri Lanka is home to the rare cobalt blue spinel, but they mine the whole spectrum of spinels. Pink, black, and blue spinels are common, with the blue variety containing trace amounts of zinc.
Spinels came to symbolize protection and power. Since the stones were often large, rulers throughout history were quick to claim them or go into battle for such beautiful spoils of war. These gems were often given as gifts as well.
Even one of the most-recognized gems in the world, one of the crown jewels of England, the Black Prince’s ruby, is a spinel. From the 1300s to the late 1700s, British rulers thought the stone was a ruby, but chemical tests by mineralogist Jean Baptiste Louis Rome de Lisle in the 1780s revealed its true origin..
If you’re partial to semi-opaque stones, you might fall in love with sardonyx. This ancient birthstone is a variety of chalcedony, which is a crystalline silica mineral made of quartz and moganite.
Sardonyx is made of sard and onyx that form attractive parallel bands across the stone. Sard is a brown-red chalcedony rich in iron oxide, while onyx is a chalcedony with black and white parallel bands. Sardonyx is a russet onyx colored with red, brown, white, or orange.
This eye-catching stone has a hardness of 7 on the Mohs scale, making it equivalent to peridot for durability. Although not as hard as some precious gems, sardonyx is perfectly structured for carving.
Sardonyx's History and Symbolism
Sardonyx has been used as a carving stone for miniature reliefs and symbols for thousands of years. As far back as ancient Egypt, people had sardonyx pieces as jewelry and symbols of protection. Often, the person or symbol carved into the stone was called upon to bring the wearer protection in battle or everyday life.
Soldiers in ancient Greece and Rome often wore carved sardonyx with images of their favorite gods for protection — Hercules as the Greek god of strength and heroes, and Mars as the Roman god of war. The stone became a symbol of courage and happiness, but also one of willpower, energy, and confidence. People also believed that sardonyx could fight depression and sadness and help give its bearer clear, reasoned thinking.
Beyond jewelry, Romans often used sardonyx for their personal seals and signet rings because it would keep its shape and detailing when dipped in hot wax.
India has been the world’s largest source of sardonyx, even in the Egyptian and Roman eras, although the Egyptians also mined a small amount in the Stela Ridge mine. Today, India remains a prime source for the stone, but sardonyx also comes from Brazil, Uruguay, Czech Republic, the United States, Germany, Slovakia, and Madagascar.
How to Wear Peridot, Sardonyx, and Spinel Gemstones
You can wear peridot in any type of jewelry, although some types like peridot rings may need more care to avoid scratches. Peridot can be cut in any shape, and it even allows for custom cuts like to bring out its sparkle.
Popular spinel shapes include triangle, octagon, round, pear, and square. Thanks to their excellent durability, spinel gems work well in all jewelry styles, whether as a spinel ring set in gold or platinum or as a custom designed spinel necklace with other gems.
Sardonyx is often cut in a cabochon for sardonyx rings, bracelets, necklaces, or earrings. You can also wear this attractive stone with intricate designs in sardonyx cameo or intaglio styles.
Are There Alternatives to These Gemstones?
If you’re looking for another way to celebrate your birth month, consider the zodiac signs. If you’re born between August 1st and August 23rd, you’re a Leo with an onyx stone. From August 24th to 31st, you’re a Virgo with a carnelian stone. Both onyx and carnelian share some similarities with the sardonyx, whether in base material or coloration.
Whichever one you choose, you’ll have plenty of ways to enjoy your beautiful August birthstone. Talk to one of our knowledgeable Brinkers associates for help picking the perfect piece for yourself or someone you love.