The July birthstone, ruby, holds a distinguished place in the realm of gemology, symbolizing passion, vitality, and nobility. Revered for centuries, ruby's fiery red hue has captured the imagination of cultures across the globe. This article delves into the rich history, geological properties, and cultural significance of ruby and its secondary July birthstones—onyx and turquoise. We explore how these gemstones have evolved in their roles as birthstones, their symbolic meanings, and practical considerations for care and appreciation.
The Historical Significance of the July Birthstone
Ruby: The King of Gemstones
Ruby, the primary birthstone for July, has been cherished since antiquity. Known as the "King of Gemstones," ruby has adorned the crowns and regalia of monarchs and warriors alike. Its vibrant red color symbolizes power, courage, and vitality. Historical records indicate that ruby was used in ancient civilizations such as Egypt, India, and China, where it was believed to possess protective and invigorating properties.
Before the formal adoption of ruby as the July birthstone in 1912 by the Jewelers of America, both onyx and turquoise were recognized as appropriate gemstones for the month. This shift underscores the evolving nature of birthstone traditions, influenced by cultural exchanges and the standardization of gemstone practices in the early 20th century.
Onyx and Turquoise: Secondary Birthstones of July
Onyx, particularly the sardonyx variety, has been linked to the month of July in various cultural calendars. Sardonyx, characterized by alternating bands of white chalcedony and sard (a darker carnelian), is believed to instill bravery and strength. In the ancient Russian calendar, sardonyx served as a zodiac stone for Leo, a sign that partially overlaps with July.
Turquoise, another secondary birthstone for July, is celebrated for its unique green-to-blue hues and its historical significance in cultures such as the Egyptians, Chinese, and Native Americans. Turquoise is believed to bring clarity of mind and spiritual discernment. While it is more commonly associated with December as a birthstone, its inclusion in July traditions highlights its versatile symbolism and enduring appeal.
Geological Formation and Sources of Ruby, Onyx, and Turquoise
Ruby: A Product of High Pressure and Heat
Ruby is a variety of the mineral corundum, composed of aluminum oxide (Al₂O₃) with trace amounts of chromium or vanadium, which give it its characteristic red color. The formation of ruby occurs under high-pressure and high-temperature conditions deep within the Earth's crust. These conditions cause the mineral to crystallize into hexagonal, flat tabular shapes, which are ideal for various ornamental cuts.
Ruby is one of the hardest minerals, second only to diamond on the Mohs scale with a rating of 9. This hardness contributes to its durability and makes it suitable for everyday wear in jewelry. However, rubies can be sensitive to thermal shock and require careful handling during processing and cleaning.
The most notable sources of ruby include:
- Myanmar (Burma): Known for producing some of the finest and most valuable rubies, particularly the "Pigeon's Blood" variety.
- India: Historically significant for ruby mining and trade.
- Sri Lanka: Produces high-quality rubies with a deep red color.
- Madagascar: A major source of ruby in the 20th and 21st centuries.
Onyx: A Chalcedony with Striking Patterns
Onyx is a type of chalcedony, a microcrystalline variety of quartz composed primarily of silicon dioxide (SiO₂). It is formed in sedimentary and volcanic rock environments where silica-rich solutions precipitate and form layered deposits. The sardonyx variety, associated with July, features distinct white and red bands, with the white layers composed of chalcedony and the red layers of sard.
Onyx has a Mohs hardness of 6.5–7, making it relatively durable for jewelry use. It is often used in carvings, cabochons, and beads, as its smooth texture and layered appearance make it ideal for ornamental purposes.
Turquoise: A Hydrated Phosphate Mineral
Turquoise is a hydrated phosphate of aluminum and copper, with the chemical formula Al₂(OH)₃PO₄. It forms in the oxidized zones of copper deposits and is typically found in arid regions where it can absorb water and change color over time. Turquoise is known for its unique blue to green hues, which vary based on the concentration of copper and aluminum.
With a Mohs hardness of 5–6, turquoise is relatively soft and porous, requiring careful handling and cleaning to avoid damage. It is often stabilized or treated to enhance its color and durability for use in jewelry.
Notable sources of turquoise include:
- Nevada and Arizona (United States): Known for high-quality turquoise.
- Iran: A historical center for turquoise mining and trade.
- China: A major source of turquoise, particularly in the Qinghai region.
- Mexico: Known for its vibrant turquoise deposits.
Gemological Properties of the July Birthstones
Ruby
- Chemical Composition: Aluminum oxide (Al₂O₃) with trace amounts of chromium or vanadium.
- Hardness: 9 on the Mohs scale.
- Refractive Index: 1.76–1.78.
- Luster: Vitreous (glassy).
- Color: Red, ranging from deep crimson to lighter shades.
- Clarity: Rubies can be included, with inclusions often referred to as "silk," which can enhance their appearance.
- Cut: Available in various cuts, including round, oval, princess, and emerald cuts.
- Carat Weight: High-quality rubies are available in various sizes, with larger stones being rarer and more valuable.
Onyx
- Chemical Composition: Silicon dioxide (SiO₂).
- Hardness: 6.5–7 on the Mohs scale.
- Refractive Index: 1.48–1.53.
- Luster: Waxy to greasy.
- Color: White, black, and banded varieties (such as sardonyx).
- Clarity: Typically opaque.
- Cut: Often cut as cabochons, beads, or carved designs.
- Carat Weight: Available in various sizes, with larger stones being more common.
Turquoise
- Chemical Composition: Hydrated phosphate of aluminum and copper (Al₂(OH)₃PO₄).
- Hardness: 5–6 on the Mohs scale.
- Refractive Index: 1.61–1.65.
- Luster: Waxy to greasy.
- Color: Blue to green, often with matrix patterns.
- Clarity: Opaque.
- Cut: Commonly cut as cabochons.
- Carat Weight: Typically available in small to medium sizes.
Symbolism and Metaphysical Beliefs
Ruby
Ruby has long been associated with passion, love, and vitality. In ancient times, it was believed to have protective properties and was worn by warriors and rulers to invoke courage and success. Ruby was also thought to enhance the heart chakra, promoting emotional balance and deepening love and compassion.
Modern metaphysical beliefs attribute ruby with the ability to stimulate energy, enhance confidence, and promote emotional healing. It is considered a stone of transformation and is often used in meditation to access higher states of consciousness.
Onyx
Onyx is traditionally associated with strength, protection, and emotional balance. In ancient times, it was believed to provide courage and ward off negative energies. Sardonyx, in particular, is thought to enhance bravery and help individuals overcome fear and anxiety.
Modern metaphysical practices view onyx as a grounding stone that promotes stability and resilience. It is often used to manage stress and support emotional well-being.
Turquoise
Turquoise is revered for its calming and protective properties. It is believed to promote clarity of mind, enhance communication, and support spiritual growth. In Native American traditions, turquoise is considered a sacred stone that connects the earth and sky, representing the balance between the physical and spiritual realms.
Modern metaphysical beliefs associate turquoise with the throat and heart chakras, promoting honest communication and emotional healing. It is also considered a stone of transformation and is used to support personal growth and self-discovery.
Care and Cleaning of the July Birthstones
Ruby
Ruby is one of the hardest gemstones and is generally easy to care for. However, it can be sensitive to thermal shock and should be protected from sudden temperature changes. To clean ruby jewelry, use a soft cloth and warm soapy water. Ultrasonic and steam cleaners are typically safe for untreated, heat-treated, and lattice diffusion-treated rubies.
Avoid using harsh chemicals or abrasive cleaners, as these can damage the surface or inclusions of the gemstone. When storing ruby jewelry, keep it in a separate compartment to prevent scratching from harder gemstones.
Onyx
Onyx should be handled with care due to its moderate hardness and porous nature. Avoid exposure to harsh chemicals and abrasive materials. Clean onyx with warm soapy water and a soft cloth. Avoid using ultrasonic cleaners, as they can damage the surface or cause the stone to crack.
When storing onyx jewelry, keep it in a soft cloth or padded compartment to prevent scratches. Avoid exposing onyx to prolonged sunlight, as it can cause fading or discoloration.
Turquoise
Turquoise is relatively soft and porous, requiring careful handling and cleaning. Avoid exposing turquoise to harsh chemicals, heat, or prolonged sunlight, as these can cause fading or damage. Clean turquoise with a soft cloth and warm soapy water. Avoid using ultrasonic cleaners, as they can cause the stone to dry out or crack.
When storing turquoise jewelry, keep it in a cool, dry place away from direct sunlight. Use a soft cloth or padded compartment to prevent scratches and damage.
Conclusion
The July birthstone, ruby, is a gemstone of enduring beauty and historical significance. Its vibrant red color and symbolic associations with passion, vitality, and nobility have made it a cherished gemstone across cultures and eras. Alongside ruby, onyx and turquoise serve as secondary July birthstones, each bringing its own unique properties and symbolism.
Understanding the geological properties, historical uses, and care requirements of these gemstones enhances their appreciation and ensures their longevity in jewelry and collections. Whether as a personal birthstone or a gift for a loved one, the July birthstones continue to captivate and inspire with their timeless allure.