August Birthstone Spotlight: Peridot, Sardonyx and Spinel

June isn’t the only month that gets three birthstones. Bestowed upon those with August birthdays are the gemstones peridot, sardonyx and spinel. Each gemstone is vastly unique from the other and gives August babies a number of options to choose their perfect look! Read on for details on each August birthstone.


Peridot is the primary August birthstone. A gem variety of the mineral olivine, peridot ranges from yellowish green to greenish yellow and has been often mistaken for emerald and topaz throughout history. In fact, some historians speculate that Cleopatra’s vast emerald collection was actually comprised (partially) of peridot.

Not only is peridot the August birthstone, but it’s also the 15th anniversary gemstone. This is a great gift option for every budget, depending on the size of the peridot. While large, grass-green peridots are more expensive, there are plenty of smaller stones that would fit a smaller budget.


Sardonyx is the original gemstone — the OG, if you will — assigned as the August birthstone. When peridot joined the party, it became the primary August birthstone ahead of sardonyx. As the name suggests, sardonyx combines alternating layers of sard and onyx. These two types of mineral chalcedony separate to create reddish and white zerbra stripes. The finest examples of sardonyx display sharp contrasts between layers.

According to the American Gem Society, “sardonyx is widely available and relatively inexpensive as gems, beads, and jewelry. It is often carved into cameos, intaglios, and brooches to show the color contrast between layers.”
Courtesy of GIA.


Remember how we said the ruby is the most valuable colored gemstone besides diamonds? Well, if you’re looking for a budget-friendly option for a ruby, that’s where the spinel gemstone comes in handy. It comes in a wealth of colors, including intense red, and is less pricey.

Often mistaken for other gemstones throughout history, the spinel has been dubbed “the great imposter.” In fact, one of the most famous “rubies” in the world, the Black Prince’s Ruby, in the British Imperial Crown is actually a red spinel.
Courtesy of GIA.

Not only is the gemstone strikingly beautiful, it carries great historical meaning. Just how great is its historical meaning? We can thank spinel for the study of gemology! As a result of the spinel’s similarity to ruby, people began to study the gemstones and their differences. Without spinel, we may not even have birthstones!