The gemstone associated with those born on August 12th is peridot, a gem celebrated for its distinctive and luminous green hue. Peridot holds a unique position in the world of gemology, not only as the modern primary birthstone for the month of August but also as a stone with a storied past that spans millennia. Its color, ranging from fresh lime to deep olive, is a direct result of its chemical composition, setting it apart from other green gems. This article provides a comprehensive exploration of peridot, detailing its historical journey from ancient civilizations to its current status, its geological origins and sources, its specific gemological properties, the symbolism it carries, and the practical care required to maintain its beauty. By examining these facets, we can appreciate why peridot continues to be a cherished gem for collectors, jewelers, and those seeking a connection to a stone of historical and personal significance.
History and Lore
The history of peridot is as rich and colorful as the gemstone itself. Its name is derived from the French word "peritot," which is believed to be a variation of the Arabic word "faridat," meaning "gem." This etymology underscores the gem’s long-standing appeal across diverse cultures. For centuries, peridot has been mistaken for other green gemstones, including emerald and topaz. This confusion is particularly notable in medieval European cathedral treasures, where many stones originally identified as emeralds have since been reclassified as peridot, highlighting the gem’s historical misidentification and its eventual recognition.
One of the most significant historical uses of peridot is found in the Shrine of the Three Holy Kings in Cologne Cathedral in Germany. This ornate reliquary, dating back to the Middle Ages, is adorned with numerous peridots, demonstrating the gem’s high value and importance in religious artifacts during that period. The use of peridot in such a prominent and sacred object speaks to its esteemed status in European history.
Beyond Europe, peridot has deep roots in ancient Egyptian culture. It was known as the "gem of the sun" and was believed to offer protection against nightmares and evil spirits. The ancient Egyptians mined peridot on the island of Zabargad (also known as St. John’s Island) in the Red Sea, which was a primary source for the gem for over 3,500 years. These historical accounts confirm peridot’s long journey from ancient mines to royal and religious adornments, solidifying its legacy as a gem of antiquity.
Geological Formation and Sources
Peridot is a gem-quality variety of the mineral olivine, with the chemical formula (Mg, Fe)₂SiO₄. Its formation is geologically unique. Unlike many gemstones that form in the Earth’s crust, peridot is found in the Earth’s upper mantle. It is brought to the surface through volcanic activity, where it can be found in certain types of igneous rocks. This deep-earth origin contributes to the gem’s natural occurrence in only one primary color family—green.
The primary sources of peridot are geographically diverse. Historically, the most renowned source was the island of Zabargad in the Red Sea, which supplied the gem to the ancient world. In modern times, significant deposits are found in Arizona, USA, particularly in the San Carlos Apache Indian Reservation, which is a major commercial source. Other notable sources include Pakistan, Myanmar (Burma), and China. The gem’s formation in volcanic environments means that it is often found in basaltic rocks, and large crystals can sometimes be discovered in volcanic ash and pumice.
Gemological Properties
Peridot possesses a distinct set of gemological characteristics that define its identity and value. Its most notable property is its color. As a gem that occurs in only one color, peridot’s hue is due to the presence of iron within its crystal structure, rather than trace elements as seen in most other colored gemstones. The color can vary from yellowish-green to olive to brownish-green, depending on the iron content. The most prized shades are a vibrant lime green to a rich olive green.
Other key gemological properties include:
- Hardness: Peridot has a hardness of 6.5 to 7 on the Mohs scale, making it durable enough for everyday jewelry but requiring some care to avoid scratches.
- Refractive Index: It has a refractive index of approximately 1.65 to 1.69.
- Crystal System: It belongs to the orthorhombic crystal system.
- Specific Gravity: Its specific gravity ranges from 3.34 to 3.51.
- Cleavage: Peridot exhibits poor cleavage, meaning it is less likely to split along specific planes, which is beneficial for durability in jewelry settings.
The following table summarizes the primary gemological properties of peridot:
| Property | Description |
|---|---|
| Mineral | Olivine |
| Chemical Formula | (Mg, Fe)₂SiO₄ |
| Color | Green (yellowish-green to olive to brownish-green) |
| Hardness (Mohs) | 6.5 - 7 |
| Crystal System | Orthorhombic |
| Refractive Index | 1.65 - 1.69 |
| Specific Gravity | 3.34 - 3.51 |
| Cleavage | Poor |
Symbolism and Metaphysical Beliefs
Peridot carries a wealth of symbolism and is attributed with various metaphysical properties across different cultures and modern practices. Historically, it was believed to offer protection and to ward off evil. In contemporary metaphysical beliefs, peridot is strongly associated with the heart chakra, representing healing, joy, and the release of negative patterns. It is often called a stone of "renewal" and "abundance."
The symbolism of peridot is frequently linked to emotions and personal growth. It is said to promote emotional clarity, reduce stress, and inspire a sense of joy and confidence. For those born in August, peridot is believed to bring good luck, peace, and success. Its vibrant green color is seen as a symbol of nature’s vitality and growth, making it a popular choice for jewelry intended to uplift the spirit and encourage positive energy.
Care and Cleaning
Given its gemological properties, peridot requires specific care to maintain its brilliance and longevity. With a hardness of 6.5 to 7, it is moderately durable but can be scratched by harder materials like corundum (ruby, sardonyx) or diamond. It is also advisable to protect peridot jewelry from sharp blows and extreme temperature changes, as it can be susceptible to cracking or chipping.
For cleaning, peridot is relatively stable but should be cleaned with mild soap, warm water, and a soft brush. Ultrasonic cleaners and steam cleaners are generally not recommended, as the heat and vibrations can potentially damage the stone, especially if it has any inclusions or fractures. Storing peridot jewelry separately in a soft cloth or lined jewelry box will help prevent scratches from other gems or harder materials.
Conclusion
Peridot stands as a gemstone of remarkable beauty and historical depth. From its ancient origins in Egyptian mines to its prominent place in medieval European religious art, it has consistently been valued for its unique green color. As the modern primary birthstone for August, peridot offers a vibrant and meaningful choice for those born in the month, symbolizing joy, renewal, and protection. Its distinct gemological properties, including its iron-induced green hue and moderate hardness, make it both a fascinating subject for gem enthusiasts and a durable gem for fine jewelry. Whether appreciated for its scientific uniqueness, its rich cultural lore, or its metaphysical associations, peridot remains a timeless and radiant gem that continues to captivate.