Birthstones have long held a special place in human culture, symbolizing protection, good fortune, and personal identity. While many gemstones are cherished for their aesthetic appeal and sentimental value, a select few stand out not only for their rarity and beauty but also for their astronomical price tags. These gemstones, considered among the most expensive birthstones, captivate collectors, jewelers, and gemologists alike due to their unique properties, historical significance, and the interplay of factors like color, clarity, and origin.
This article delves into the most expensive birthstones, exploring their origins, gemological properties, cultural symbolism, and the reasons behind their extraordinary value. Drawing from a combination of historical lore, scientific data, and market insights, the following sections provide a comprehensive look at the gems that command the highest prices in the world of birthstones.
Introduction
The concept of birthstones traces its roots to biblical times, with references to twelve gemstones representing the twelve tribes of Israel. Over the centuries, this tradition evolved into a system where each month of the year is associated with a specific gemstone. Today, birthstones are not only celebrated for their symbolic meanings but also for their monetary value. Some of these gems, due to their rarity, color, and historical prestige, have become among the most expensive in the world.
The most expensive birthstones are not only prized for their aesthetic qualities but also for their scarcity and the interplay of geological and cultural factors that influence their value. From the color-changing marvel of alexandrite to the deep red allure of ruby, these gemstones exemplify the intersection of nature’s artistry and human fascination with the rare and the beautiful.
This article explores the top most expensive birthstones, examining their origins, gemological properties, and the reasons behind their high market value. It also touches on their historical and cultural significance, as well as practical considerations for owning and caring for these precious gems.
The Most Expensive Birthstones and Their Value
1. Alexandrite: The Color-Changing Wonder
Alexandrite holds the distinction of being the most expensive birthstone, with prices ranging from $15,000 to $70,000 per carat for high-quality specimens. Discovered in the Ural Mountains of Russia in 1830, alexandrite was named after Czar Alexander II, whose birthday coincided with its discovery. This gemstone is a variety of the mineral chrysoberyl and is known for its remarkable color change—shifting from a bluish-green in daylight to a purplish-red under incandescent light. This phenomenon, known as the "alexandrite effect," is extremely rare and contributes to its desirability.
Alexandrite’s value is further enhanced by its scarcity. Natural alexandrite is found in only a few locations worldwide, including Brazil, Sri Lanka, and Madagascar. The finest examples, which display the most vivid color change, are especially rare and command the highest prices. Alexandrite is one of June’s birthstones and is often referred to as an "emerald by day and a ruby by night," a poetic description that underscores its unique optical properties.
2. Ruby: The King of Gems
Ruby, the birthstone for July, is another gemstone that commands a premium price. High-quality rubies can fetch $3,500,000 per kilogram, with individual stones selling for millions of dollars. The most famous example is the 15.99-carat Jubilee Ruby, which sold for $14.2 million in 2016, making it the most expensive gemstone sold at auction in the United States.
Rubies are a variety of the mineral corundum, which also includes sapphires. What sets rubies apart is their deep red color, caused by trace amounts of chromium. The finest rubies are found in Myanmar (formerly Burma), where the "pigeon’s blood" color—intense red with a slight blue secondary hue—is considered the most valuable. Ruby’s value is also influenced by its hardness (9 on the Mohs scale), durability, and historical significance, as it has been prized for centuries in royal collections and religious artifacts.
3. Sapphire: The Royal Blue Stone
Sapphires, particularly the deep blue variety, are among the most expensive birthstones. While diamonds are often perceived as the most valuable gemstone, sapphires can surpass them in price, especially when considering rare and high-quality specimens. Blue sapphires, which are a variety of corundum, can cost $2,000 per carat or more, with exceptional examples fetching prices in the millions.
Sapphires are the birthstone for September and come in a wide range of colors, including pink, yellow, and green. However, the blue sapphire, especially those from Kashmir, is considered the most valuable. Kashmir sapphires are known for their velvety blue color and are highly sought after by collectors. The rarity of these gems, combined with their hardness (9 on the Mohs scale) and historical association with royalty, contributes to their high value.
4. Tanzanite: The Gem of a Single Country
Tanzanite, the birthstone for December, is a rare gemstone found only in a small region of Tanzania. It is a variety of the mineral zoisite and is known for its vivid purple to blue color. Tanzanite can cost $1,000,000 per kilogram, with some of the finest examples selling for over $3.3 million. The gemstone was discovered in 1967 and quickly gained popularity due to its unique color and the fact that it is only found in one location in the world.
Tanzanite’s value is largely due to its limited availability and the geological conditions required for its formation. It forms under specific heat and pressure conditions in metamorphic rocks and is often heat-treated to enhance its color. Tanzanite has a hardness of 6–6.5 on the Mohs scale, making it less durable than sapphires or rubies, which limits its use in everyday jewelry. Instead, it is often reserved for display pieces and collectible jewelry.
5. Emerald: The Green Treasure
Emerald, the birthstone for May, is a gemstone with a rich history and a deep green color caused by trace amounts of chromium or vanadium. Emeralds can cost $4,000 per carat, with the most exceptional examples reaching prices in the millions. The most famous emerald is the 100.54-carat Daria-i-Nur ("Sea of Light") in Iran, which is estimated to be worth hundreds of millions of dollars.
Emeralds are a variety of the mineral beryl and are known for their inclusions, which are often considered part of their character. The finest emeralds come from Colombia, where the geological conditions are ideal for producing high-quality stones. Emeralds have a hardness of 7.5–8 on the Mohs scale, making them relatively durable but still requiring careful handling to avoid damage.
6. Tourmaline: The Rainbow Stone
Tourmaline, particularly the blue variety known as Paraíba tourmaline, is another gemstone that commands a high price. The most valuable tourmalines, such as the Ethereal Carolina Divine Paraíba, can be valued at over $125 million for a single stone. Tourmaline is the birthstone for October and comes in a wide range of colors, including green, blue, red, and even rainbow-colored stones.
Blue tourmaline, especially the Paraíba variety, is exceptionally rare and is found in only a few locations in Brazil. The blue color is caused by trace amounts of copper and manganese, and the finest specimens exhibit a vivid neon blue hue. Tourmaline has a hardness of 7–7.5 on the Mohs scale, making it relatively durable, but it is still sensitive to heat and chemicals, which can affect its color and clarity.
Historical and Cultural Significance
The allure of the most expensive birthstones is not solely based on their physical properties but also on their historical and cultural significance. Many of these gems have been associated with royalty, power, and mysticism throughout history. For example, rubies were believed to bring protection and good fortune in ancient times, while sapphires were associated with divine favor and wisdom.
In medieval Europe, gemstones were often incorporated into religious artifacts and royal regalia. The deep blue sapphire, for instance, was thought to represent the heavens and was used in crowns and scepters. Similarly, emeralds were prized by the Incas and Aztecs for their vibrant green color, which symbolized life and fertility.
In modern times, the popularity of these gemstones has been influenced by marketing and celebrity culture. Diamonds, for example, became a symbol of love and commitment largely due to the efforts of the De Beers company in the 20th century. While diamonds are not as rare as rubies or emeralds, their perceived value has been driven by demand and cultural narratives.
Gemological Properties and Scientific Characteristics
Understanding the gemological properties of the most expensive birthstones helps explain their value and rarity. These properties include hardness, chemical composition, refractive index, and color formation.
| Gemstone | Hardness (Mohs) | Chemical Composition | Color Cause | Rarity |
|---|---|---|---|---|
| Alexandrite | 8.5–9 | BeAl2O4 | Chromium and Iron | Very rare |
| Ruby | 9 | Al2O3 with Cr | Chromium | Rare |
| Sapphire | 9 | Al2O3 with Fe/Ti | Iron and Titanium | Moderate |
| Tanzanite | 6–6.5 | Ca2Al3SiO6(OH)2 | Vanadium | Extremely rare |
| Emerald | 7.5–8 | Be3Al2Si6O18 | Chromium or Vanadium | Rare |
| Tourmaline | 7–7.5 | Complex silicate (varies by type) | Copper and Manganese | Rare (Paraíba) |
Color and Light
One of the most important factors in determining a gemstone’s value is its color. The most expensive birthstones are often those with the most intense and saturated colors. For example, the deep red of a ruby or the vivid blue of a sapphire is highly desirable. Color is influenced by trace elements in the gemstone’s chemical composition, such as chromium in rubies or vanadium in tanzanite.
In addition to color, the way a gemstone interacts with light also affects its value. Alexandrite’s color-changing properties, for instance, are a result of its ability to absorb and reflect different wavelengths of light depending on the light source. This phenomenon is not only rare but also visually striking, making alexandrite a highly sought-after gemstone.
Clarity and Inclusions
Clarity refers to the presence of inclusions or internal flaws within a gemstone. While some inclusions can detract from a gemstone’s value, others are considered characteristic of certain gemstones. For example, emeralds are often valued for their inclusions, which are seen as proof of their natural origin. In contrast, diamonds are graded on clarity, with the most valuable stones being those with no visible inclusions.
The presence and type of inclusions can also affect a gemstone’s durability and appearance. Tanzanite, for example, is known for its inclusions, which can affect its color and stability. As a result, tanzanite is often heat-treated to enhance its color and improve its clarity.
Hardness and Durability
The hardness of a gemstone, measured on the Mohs scale, is another important factor in determining its value and suitability for jewelry. Harder gemstones are more durable and less likely to scratch or wear down over time. Rubies and sapphires, both with a hardness of 9 on the Mohs scale, are among the hardest gemstones and are ideal for everyday wear.
Softer gemstones, such as tanzanite (6–6.5) and emerald (7.5–8), require more careful handling to prevent damage. Tanzanite, in particular, is sensitive to heat and chemicals and is often recommended for display rather than daily wear.
Market Value and Pricing Factors
The market value of the most expensive birthstones is influenced by a combination of factors, including rarity, quality, size, and demand. High-quality specimens, especially those with intense color and excellent clarity, command the highest prices. For example, a large, flawless ruby with a deep red color can be worth millions of dollars per carat, while a small, low-quality ruby may be worth only a few hundred dollars.
The size of a gemstone also plays a significant role in its value. Larger stones are rarer and more valuable, especially when they maintain high color and clarity. The Jubilee Ruby, for example, was valuable not only for its color but also for its size—15.99 carats is an exceptional weight for a ruby of such quality.
Demand is another key factor in pricing. Certain gemstones may become more valuable due to trends in fashion or celebrity endorsements. For example, the popularity of paraíba tourmaline surged after it was featured in high-profile auctions and worn by celebrities.
Care and Maintenance
Owning a high-value birthstone requires proper care to preserve its beauty and value. Here are some general guidelines for caring for the most expensive birthstones:
- Alexandrite: Avoid exposure to heat and chemicals. Clean with warm, soapy water and a soft brush.
- Ruby and Sapphire: These are durable gemstones but should still be cleaned carefully. Avoid using steam cleaners or ultrasonic cleaners if the stone has inclusions.
- Tanzanite: Due to its lower hardness and sensitivity to heat, tanzanite should be cleaned with a soft cloth and mild soap. Avoid exposure to direct sunlight for extended periods.
- Emerald: Emeralds are sensitive to heat and should be cleaned with a soft cloth and mild soap. Avoid using steam cleaners or ultrasonic cleaners, as these can damage the stone.
- Tourmaline: Tourmaline is relatively durable but should still be cleaned with care. Avoid exposure to heat and chemicals, especially for Paraíba tourmaline.
Proper storage is also important. High-value gemstones should be stored in a cool, dry place away from direct sunlight and other gemstones to prevent scratching. It is also advisable to have valuable gemstones appraised regularly to ensure their value and condition.
Conclusion
The most expensive birthstones are a testament to the beauty, rarity, and cultural significance of gemstones. From the color-changing wonders of alexandrite to the deep red allure of ruby, these gems have captivated humans for centuries. Their value is not only determined by their physical properties but also by their historical and cultural associations, making them highly sought after by collectors and jewelry enthusiasts alike.
Understanding the factors that contribute to their value—such as rarity, color, clarity, and hardness—helps explain why these gemstones command such high prices. Whether as a symbol of status, a cherished heirloom, or a valuable investment, the most expensive birthstones continue to hold a special place in the world of gemology and jewelry.