July, the month named after Julius Caesar, is steeped in historical and cultural richness. Among its many associations—ranging from national holidays like Independence Day in the United States and Canada Day to being the birth month of numerous celebrities—it also holds a special place in the world of gemology. Those born in July are particularly fortunate, for their month is represented by not one, but two remarkable birthstones: the ruby and the onyx. These gemstones have captivated people for centuries, not only for their beauty and rarity but also for their deep-rooted symbolism and historical significance.
This article explores the ruby and onyx in detail, examining their geological properties, historical and cultural meanings, and modern relevance. Whether you are a gemstone enthusiast, a jewelry collector, or someone simply curious about the significance of these stones, this guide will provide you with a comprehensive and authoritative understanding of July’s dual birthstones.
A Glimpse into History and Lore
The association of gemstones with the months of the year dates back centuries, with roots in both ancient and medieval traditions. July’s modern birthstones—ruby and onyx—have evolved from a broader list of traditional stones that once included carnelian, sapphire, and sardonyx. The transition from traditional to modern birthstones reflects changes in cultural preferences, gemstone availability, and the standardization of birthstone lists by organizations like the Jewelers of America in the mid-20th century.
Ruby: The King of Precious Stones
Ruby, the most prominent and widely recognized July birthstone, has long been revered as the “king of precious stones.” Its deep red hue symbolizes passion, vitality, and power, making it a favorite among royalty and nobility throughout history. The name ruby is derived from the Latin word ruber, meaning “red,” a color that has been associated with love and life force since antiquity.
In ancient India, ruby was considered the ultimate gemstone, not only for its rarity and hardness—second only to diamond—but also for its perceived mystical powers. It was believed to bring protection, health, and prosperity to its wearer. Burmese warriors, for instance, carried rubies into battle, believing they granted invincibility. In medieval Europe, rubies were thought to bestow wisdom, health, and success in love, further reinforcing their status as a gemstone of power and nobility.
Onyx: A Symbol of Strength and Protection
While ruby commands attention with its fiery red color, onyx offers a more subdued yet equally powerful presence. Known for its smooth, banded appearance, onyx has been valued for its protective properties and symbolic meaning. Historically, it has been used as a talisman to promote self-awareness, strength, and emotional balance.
Onyx is particularly associated with the idea of duality—its black and white bands are often interpreted as a representation of balance and harmony. This symbolism makes it a popular choice for jewelry that signifies enduring relationships, as it is also the gemstone associated with the 7th wedding anniversary. In ancient times, onyx was believed to ward off negative energies and bring a sense of calm and stability to the wearer.
Geological Formation and Sources
Understanding the geological origins of July’s birthstones provides insight into their rarity, beauty, and value.
Ruby: A Product of Extreme Conditions
Ruby is a variety of the mineral corundum, which is composed of aluminum oxide (Al₂O₃). The red color of ruby is due to trace amounts of chromium, which replaces some of the aluminum atoms in the crystal lattice. The more chromium present, the more intense the red color. The finest rubies exhibit a deep red with a slight purplish hue, a color known in the trade as “pigeon’s blood.”
Ruby forms under extreme geological conditions—specifically, in metamorphic environments where heat and pressure transform existing minerals into new, more stable forms. The most famous ruby deposits are found in Myanmar (formerly Burma), where the Mogok Valley has been a primary source of high-quality rubies for centuries. Other notable sources include Thailand, Sri Lanka, Afghanistan, and Madagascar.
The rarity of ruby is partly due to the difficulty of finding gem-quality specimens. Most corundum is colorless, and only when trace elements like chromium are present does it develop the rich red color that defines ruby. The combination of geological rarity and historical demand has made ruby one of the most valuable and sought-after gemstones in the world.
Onyx: A Silica-Based Sedimentary Stone
Unlike ruby, onyx is a type of chalcedony, which is a form of quartz (SiO₂) that belongs to the broader family of silica-based minerals. Onyx is typically characterized by its distinct banded layers, which can appear in various colors, including black and white, brown and white, or even multicolored.
Onyx forms in sedimentary environments, often in the cavities of volcanic rock. Over time, mineral-rich water seeps into these cavities, depositing layers of silica that harden into the banded patterns seen in onyx. This slow process results in the stone’s smooth texture and durability.
Onyx is relatively abundant compared to ruby, and it is found in several parts of the world, including Brazil, India, Uruguay, and the United States. However, the quality and appearance of onyx can vary significantly, with black onyx being the most commonly associated with the July birthstone.
Gemological Properties and Characteristics
To appreciate the beauty and durability of July’s birthstones, it is essential to understand their gemological properties.
Ruby’s Scientific Profile
- Chemical Formula: Al₂O₃ (aluminum oxide)
- Crystal System: Trigonal
- Hardness: 9 on the Mohs scale
- Color: Red, with the finest specimens displaying a deep red with a purplish hue (known as “pigeon’s blood”)
- Luster: Vitreous (glassy)
- Specific Gravity: 3.95–4.05
- Refractive Index: 1.76–1.78
- Cleavage: Basal (perfect), which means it can split easily along certain planes
- Inclusions: Common inclusions such as rutile needles (“silk”) are often seen in rubies and can enhance their value by proving their natural origin
Ruby’s high hardness makes it suitable for a wide range of jewelry applications, including rings, pendants, and earrings. However, due to its perfect cleavage, it must be cut and set with care to avoid damage.
Onyx’s Scientific Profile
- Chemical Formula: SiO₂ (silicon dioxide)
- Crystal System: Trigonal (as a variety of quartz)
- Hardness: 6.5–7 on the Mohs scale
- Color: Typically black, white, or banded
- Luster: Waxy to dull
- Specific Gravity: 2.60–2.64
- Refractive Index: 1.48–1.53
- Cleavage: None; fractures conchoidal (shell-like)
- Inclusions: May contain minor inclusions, but these are generally not visible to the naked eye
Onyx is less hard than ruby, which makes it more susceptible to scratches and abrasions. However, its durability is still sufficient for most jewelry uses, especially when properly cared for. The absence of cleavage makes onyx less prone to splitting than ruby, though it can still be damaged if exposed to harsh chemicals or abrasive materials.
Symbolism and Metaphysical Beliefs
Both ruby and onyx have long been associated with symbolic meanings and metaphysical properties, reflecting their roles in both ancient and modern belief systems.
Ruby: A Stone of Passion and Power
Ruby has been revered for centuries as a symbol of passion, vitality, and protection. In ancient India, it was believed to bring health, prosperity, and invincibility to warriors. The idea that ruby could predict danger or ward off misfortune was also common in medieval Europe, where it was thought to be a protective talisman.
In modern times, ruby continues to be associated with love and romance. Its deep red color is often linked to the heart chakra, symbolizing emotional strength and connection. Wearing ruby is believed to enhance self-confidence, stimulate the life force, and promote a sense of vitality and enthusiasm for life.
Onyx: A Stone of Strength and Balance
Onyx is often seen as a grounding and protective stone. It is believed to help individuals maintain emotional balance and resist negative influences. In ancient times, it was used as a talisman to promote strength, endurance, and self-awareness.
Modern metaphysical practitioners associate onyx with the root chakra, which is responsible for a sense of stability and connection to the physical world. It is said to help release fear, promote courage, and encourage a sense of inner strength. For this reason, onyx is often recommended for those who are undergoing significant life changes or seeking to build resilience.
Care and Maintenance
Proper care and maintenance are essential for preserving the beauty and longevity of both ruby and onyx jewelry.
Caring for Ruby
Due to its high hardness and durability, ruby is relatively easy to care for. However, its perfect cleavage means it can be damaged if struck in the wrong direction. To clean ruby jewelry, use warm water and a mild detergent. Gently brush the gemstone with a soft cloth or a soft-bristled brush to remove dirt and debris. Avoid using ultrasonic cleaners, as they can cause damage to the stone or its setting.
When storing ruby jewelry, keep it in a soft pouch or separate compartment to prevent scratching from other gemstones. Avoid exposing ruby to extreme heat or sudden temperature changes, as this can cause internal stress and damage the stone.
Caring for Onyx
Onyx requires a bit more care due to its lower hardness and porous nature. While it is durable, it can be scratched by harder gemstones and is sensitive to abrasive materials. To clean onyx, use a soft cloth and a small amount of warm, soapy water. Avoid soaking the stone in water for extended periods, as it can absorb moisture and become discolored or damaged.
Onyx should also be kept away from harsh chemicals, including household cleaners and perfumes. Store onyx jewelry in a dry, cool place, preferably in a soft pouch to prevent scratches. Avoid exposing onyx to direct sunlight for prolonged periods, as this can cause fading or discoloration.
Conclusion
July’s dual birthstones—ruby and onyx—offer a unique combination of beauty, symbolism, and historical significance. Ruby, with its deep red color and association with passion and power, has been cherished by royalty and warriors alike for centuries. Onyx, with its grounding properties and protective symbolism, provides a complementary balance to ruby’s fiery energy. Together, these gemstones represent the rich cultural and geological heritage of July, making them a fitting tribute to those born in this month.
Whether you choose ruby for its vibrant color and regal allure or onyx for its calming presence and protective qualities, both stones are sure to make a meaningful addition to any jewelry collection. As you explore the world of birthstones, remember that each gemstone tells a story—one that spans across time, cultures, and traditions. The ruby and onyx are more than just beautiful stones; they are enduring symbols of strength, passion, and the enduring power of nature.