The gemstone known as peridot occupies a unique position in the world of gemology, standing at the intersection of deep earth geology, extraterrestrial origins, and a rich tapestry of historical confusion and cultural reverence. Distinct from most gemstones, peridot is the gem variety of the mineral olivine, a primary constituent of the earth's upper mantle. Its journey to the surface is a violent and spectacular one, often arriving as molten crystals that fall to the earth in the shape of a tear drop. This unique formation process has imbued the stone with a mythology that spans millennia, from the tears of the volcano goddess Pele in ancient Hawaii to the alleged components of Cleopatra's famous emerald collection. To understand peridot is to explore a gemstone that is literally made of "stardust," found in pallasite meteorites and even in comet dust returned by the Stardust robotic space probe in 2005.
The identity of peridot has been a source of confusion for centuries, often mistaken for emeralds, apatite, demantoid garnet, chrome diopside, chrome tourmaline, moldavite, and green zircon. This confusion extends to significant historical artifacts. The gems adorning the shrine of the Three Holy Kings in Cologne Cathedral, completed in 1225, were long believed to be emeralds but have since been demonstrated to be peridots brought back from the Near East by crusaders. Similarly, the stones in St. Edward's Crown, made for the coronation of England's Charles II in 1661, were identified as peridots. This historical misidentification highlights the visual similarity between the intense green of emerald and the yellowish-green of peridot, leading historians to suggest that some of Cleopatra's famous emerald collections might have actually been peridots.
Geologically, peridot is a gem variety of olivine, with the chemical formula (MgFe)2SiO4. Unlike most gems that derive their color from trace impurities, peridot's color is intrinsic, caused by iron within the crystal lattice, resulting in its characteristic yellowish-green hue. This intrinsic coloration, combined with its formation in the upper mantle, gives the stone a connection to the deepest parts of the planet and the outer reaches of the solar system. With a Mohs hardness ranging from 6.5 to 7, peridot is durable enough for jewelry but requires careful handling due to its brittleness and strong cleavage.
The historical journey of peridot is as fascinating as its geological origins. In the medieval period, scholars believed peridot offered special powers. According to De Lapidibus (Of Gemstones), written by Bishop Marbode in the late 11th century, peridot could dispel the terrors of the night if set in gold. To use it as protection from the wiles of evil spirits, the stone had to be pierced and strung on the hair of an ass and then attached to the left arm. The Romans were also big fans of this gem, nicknaming it the "evening emerald" because of its perceived ability to almost glow in the dark. They believed that goblets and sword handles encrusted with peridots would transform what one drank into a potion of greatness and grant power on the battlefield.
As the industrial revolution and political upheavals of the 19th century changed the jewelry landscape, peridot saw a resurgence in popularity. Less expensive gemstones became a good alternative to their precious counterparts. Peridot was particularly popular in the 1830s and 1840s, and it became quite common around 1890 when the mines on Île Saint-Jean were revived. During the Belle Époque and Art Nouveau periods, jewelers like René Lalique utilized peridot in pieces such as the "Noisettes" necklace (1899-1900), which combined eleven peridots with diamonds, gold, and translucent enamel. The stone was also found on pendants and necklaces, often accompanied by pearls and set in 9 or 14kt gold settings.
In modern times, the Field Museum of Natural History in Chicago began its gem collection in 1893 with the purchase of a Tiffany collection of jewels that included a massive 154-carat peridot, almost 2.5 inches long, named "The Green Goddess." In 2008, the museum selected the Chicago jewelry design firm Lester Lampert to create a setting for this historic gemstone. Today, peridot serves as the official birthstone for August and the gemstone for the 15th wedding anniversary.
Geological Origins and Cosmic Connections
The geological narrative of peridot is one of extreme heat and deep-earth origins. As a gem variety of the mineral olivine, it is found in peridotite rock from the earth's upper mantle. The mechanism of its arrival on the surface is dramatic; the molten crystals fall to the earth in the shape of a tear drop. This specific formation process has led to powerful cultural interpretations. Ancient Hawaiians believed that these stones were the tears of the volcano goddess Pele. This mythological connection to volcanism underscores the stone's fiery origin.
Beyond the earth's crust, peridot has a truly extraterrestrial history. It is found in pallasite meteorites, which are remnants of our solar system's birth. In 2005, peridot was found in comet dust brought back from the Stardust robotic space probe. This discovery reinforces the idea that peridot is "stardust," linking human adornment directly to the formation of the solar system. Large, strongly-colored examples can be spectacular, while attractive smaller gems are available for jewelry at all price points.
Historical Confusion and Artifacts
The history of peridot is deeply entangled with its frequent misidentification as emerald. This confusion is not merely academic but affects the attribution of some of history's most famous jewels. Some historians suggest that Cleopatra's famous emerald collections might have been peridot. This possibility arises because the two stones share a greenish hue, though the specific yellowish tint of peridot can be mistaken for the rich green of emerald in certain lighting.
The confusion extends to religious and royal regalia. The gems adorning the shrine of the Three Holy Kings in Cologne Cathedral, completed in 1225, were long thought to be emeralds. They have since been demonstrated to be peridots, brought back from the Near East by crusaders. The shrine itself is a masterpiece of medieval craftsmanship, featuring protruding peridots at the top. Similarly, the peridots in St. Edward's Crown, made for the coronation of England's Charles II in 1661, were likely misidentified for centuries.
In the medieval and early modern eras, the stone was used to enhance church ornaments and adorn objects of worship. The Romans, who were also big fans of this gem, nicknamed it the "evening emerald" due to its perceived ability to almost glow in the dark. This nickname reflects a belief in the stone's unique optical properties and its ability to ward off darkness.
During the 18th and 19th centuries, peridot gained popularity as a more affordable alternative to emeralds. The democratization of gemstones began in the 19th century, an era marked by political upheaval in Europe and the Industrial Revolution. In France, the fall of the First Empire in 1815 gave way to the Restoration. For the first time, fashion was no longer dictated solely by a court. As the country faced a major shortage of raw materials, jewelers vied with each other in inventiveness to create ornaments that achieved "maximum effect with minimum expense." Peridot was particularly popular in the 1830s and 1840s and became quite common around 1890 when the mines on Île Saint-Jean were revived.
The use of peridot in jewelry evolved significantly during this period. It became common in brooches, often mixed with diamonds and pale gems like amethysts and opals, which was relatively characteristic of the period. Our green stone was also found on pendants and necklaces, often accompanied by pearls and set in 9 or 14kt gold. Art Nouveau jewelers, such as René Lalique, utilized the stone in intricate designs like the "Noisettes" necklace, combining peridots with diamonds, gold, and translucent enamel.
Physical Properties and Gemological Characteristics
To understand the stone's value and care, one must examine its specific gemological properties. Peridot is distinct because its color is intrinsic, caused by iron within the crystal lattice, rather than by external impurities. This iron content gives it its signature yellowish-green color. The stone possesses a specific gravity of 3.34, a refractive index ranging from 1.65 to 1.69, and a birefringence of 0.035 to 0.038. Its hardness on the Mohs scale is 6.5 to 7, making it suitable for jewelry but requiring care due to its brittleness and strong cleavage.
The presence of inclusions is a key factor in peridot grading. While peridot gems with good clarity are not rare, blurry or cloudy versions of this gemstone must be avoided. Reflective, disk-like inclusions called "lily pads" are another type of inclusion that can be seen in peridots. These inclusions are often a result of the stone's rapid crystallization. Because the stone is brittle with strong cleavage, the lapidarist must take extra care while faceting this gem. A good quality cut significantly elevates the beauty and brilliance of a peridot.
Peridot is available in an assortment of shapes and cuts, such as round, oval, pear, cushion, triangle, and marquise, among others. Step cuts like square or rectangular emerald cuts are also very popular. The cut must account for the stone's cleavage to prevent breakage during setting and wear.
Metaphysical Beliefs and Cultural Significance
The lore surrounding peridot is as rich as its geological history. Scholars of the medieval period believed that, like other gems, peridot offered special powers to the wearer. According to De Lapidibus by Bishop Marbode in the late 11th century, peridot dispelled the terrors of the night if it were set in gold. If it were to be used as a protection from the wiles of evil spirits, the stone had to be pierced and strung on the hair of an ass and then attached to the left arm.
Historically, there was an apparent belief that peridot could ward off evil spirits, and that if the stone was set in gold (and other precious metals), its capacity to bring the bearer good luck and fortune was intensified even more. In days gone by, goblets and sword handles of the wealthy and powerful landowners and aristocracy were encrusted with peridots. They believed that anything they drank from these encrusted goblets would become a potion to stimulate greatness. The same theory applied to swords, as it was thought peridot would bring power on the battlefield and strength to the bearer's legions.
Peridot has long been associated with the sun, and as such, it has been regarded as a gemstone that drives away darkness. It has also been said to relieve feelings of guilt and lessen obsession, along with helping to calm feelings of fear and anger. The stone is believed to enhance one's ability to learn new things by increasing focus and cognitive capacity, and providing the strength to persevere in challenging situations and times. Thought to increase motivation and self-worth, the stone has also been said to decrease feelings of envy in the wearer.
Although there is no scientific evidence to suggest these properties exist, it is an avenue of gemstone knowledge that deserves further exploration. Peridot has long been associated with luck, and many cultures have celebrated the unusual and mystical elements of the stone in their myths and legends. The connection to the sun and the "evening emerald" moniker suggests a belief in the stone's ability to combat darkness, both literal and metaphorical.
Quality Grading and Market Value
While there is no standardized scale to rank peridots, they can be graded into the following categories of quality based on color, clarity, and brilliance. This system helps buyers navigate the market for heirloom-quality stones versus more common examples.
| Quality Category | Color Description | Clarity | Brilliance | Rareness |
|---|---|---|---|---|
| Heirloom (AAAA) | Green | Eye Clean | Very High | Top 1% |
| Best (AAA) | Yellowish Green | Eye Clean | High | Top 10% |
| Better (AA) | Medium Yellowish Green | Slightly Included | Medium | Top 33% |
| Good (A) | Light Yellowish Green | Slightly Included | Low | Top 75% |
Heirloom quality peridots are characterized by a deep green color and eye-clean clarity. These stones are rare, representing the top 1% of available peridots. Best quality stones are yellowish-green and also eye-clean. Better and Good quality stones may show slight inclusions or have a lighter, less saturated color. Peridot gems with good clarity are not rare, but buyers must avoid blurry or cloudy versions of this gemstone, as they significantly detract from the stone's value.
The market for peridot jewelry includes a wide range of price points. Large, strongly-colored examples can be spectacular, while attractive smaller gems are available for jewelry at all price points. Vintage pieces from the 19th and early 20th centuries, such as those from the Victorian era, have become relatively rare on the market. However, with a little patience, one may find a nice piece. More common is the stone associated with amethyst on suffragette jewelry. Lovers of this gemstone will also find it easier to turn to vintage pieces from the 60s-70s.
Current market trends show a variety of settings, including prong-set, bezel-set, and knife-edge shanks. GIA certified stones are also available for those seeking verification of authenticity and quality. Whether in a solitaire pendant, a cushion-cut ring, or an Art Nouveau brooch, the stone's versatility allows it to be set in a variety of designs, from simple pendants to complex necklaces.
Conclusion
Peridot stands as a testament to the deep connections between the earth's mantle, the cosmos, and human history. From its formation in the earth's upper mantle to its discovery in meteorites and comet dust, peridot is a stone with a truly cosmic origin. Its yellowish-green hue, intrinsic to its iron content, has led to centuries of confusion with emeralds, impacting the identification of royal and religious artifacts. The stone's journey from medieval talismans and Roman "evening emeralds" to the democratized jewelry of the 19th century and the sophisticated designs of the Art Nouveau era illustrates its enduring appeal.
The gem's physical properties—its brittleness, strong cleavage, and intrinsic color—require specialized handling during faceting and setting. Yet, its durability on the Mohs scale (6.5 to 7) makes it a practical choice for daily wear. Metaphysically, it is revered for its ability to dispel darkness and bring good luck, a belief system that has persisted from ancient Hawaii to modern healing traditions.
As the birthstone for August and the gemstone for the 15th anniversary, peridot continues to be a popular choice for jewelry. Whether found in a museum collection like "The Green Goddess" or in a modern pendant, peridot remains a bridge between the deep earth, the vastness of space, and the enduring human desire for beauty and protection.