What is Tourmaline: The Most Colorful Gemstone on Earth

Tourmaline stands as one of nature’s most extraordinary semi-precious gemstones, captivating jewelry enthusiasts and collectors alike with its remarkable spectrum of colors and unique properties. From electric blues to vibrant pinks and lush greens, tourmaline’s versatility has earned it a special place in the world of gemstones. Unlike many gemstones known for a signature color, tourmaline appears in virtually every hue imaginable, earning it nicknames like the “rainbow gemstone.” Beyond its visual appeal, tourmaline possesses fascinating physical and electrical properties that have made it valuable not just for jewelry but also for various scientific and industrial applications throughout history.

Understanding Tourmaline

Tourmaline is a crystalline boron silicate mineral comprising one of the most complex mineral groups in gemology. Rather than being a single mineral, “tourmaline” refers to a family of closely related minerals with varying chemical compositions that give rise to its incredible diversity of colors and properties.

• Tourmaline’s name derives from the Sinhalese word “turmali,” which was used by merchants in Sri Lanka (formerly Ceylon) to describe mixed colored gemstones they traded. Dutch merchants introduced these colorful stones to Europe in the 17th century, using this term that eventually became the gemstone’s official name.
• The gemstone belongs to a complex group of minerals with varying amounts of aluminum, iron, magnesium, sodium, lithium, and other elements, which contribute to its vast color range and different varieties like elbaite, schorl, dravite, and liddicoatite.
• Tourmaline typically forms in long, slender crystals with triangular cross-sections that can grow to impressive sizes. These crystals can be transparent to opaque with a glass-like to resinous luster when polished, making them versatile for various jewelry applications.
• With a hardness of 7 to 7.5 on the Mohs scale, tourmaline is durable enough for everyday wear in all types of jewelry settings, including rings which receive more impact and abrasion than other jewelry pieces.
• For centuries, tourmaline was frequently confused with other gemstones – red tourmalines were mistaken for rubies, green for emeralds, and blue for sapphires. It wasn’t until the 19th century that advanced scientific analysis identified tourmaline as its own distinct mineral group.

This remarkable mineral formation explains why tourmaline continues to surprise even experienced gemologists with its range of appearances. Its combination of durability, diverse beauty, and relative affordability compared to precious gemstones makes it both practical and desirable for jewelry that can stand the test of time.

The Scientific Properties of Tourmaline Gemstones

The fascinating properties of tourmaline stem from its complex chemical structure, which allows for numerous variations that affect its appearance and behavior. This scientific foundation explains why tourmaline displays such extraordinary diversity compared to simpler gemstone minerals.

• Tourmaline’s chemical composition is defined by the general formula XY₃Z₆(T₆O₁₈)(BO₃)₃V₃W, where each letter represents different elements that can substitute for one another. This complex formula allows for countless chemical variations, which is why tourmaline appears in more colors than almost any other gemstone in the world.
• The crystal structure of tourmaline is trigonal (three-sided), forming distinctive prismatic crystals with rounded triangular cross-sections. This distinctive shape helps gemologists identify tourmaline in its rough form, even before sophisticated testing.
• Tourmaline displays remarkable pleochroism, showing different colors when viewed from different directions. For example, a single blue tourmaline crystal might appear darker blue when viewed down its length but lighter blue or even greenish when viewed from the side. Gem cutters must carefully orient the stone to showcase its best color.
• One of tourmaline’s most scientifically significant properties is its pyroelectricity and piezoelectricity. When heated or put under pressure, tourmaline generates an electrical charge on its opposite ends, making it both pyroelectric and piezoelectric. This property led Dutch jewelers to use tourmaline as “aschentrekker” (ash puller) to draw ash from their pipes.
• Tourmaline has a refractive index of 1.624-1.644, giving it good brilliance, though not as flashy as diamond. This moderate brilliance combined with its strong colors makes it especially suited for larger statement pieces where color is more important than sparkle.

These scientific properties not only contribute to tourmaline’s beauty and value in jewelry but have also made it useful in various scientific instruments, pressure sensors, and even as a material in hair appliances that claim to use tourmaline’s infrared properties for gentler styling.

Tourmaline Colors: Every Shade of the Rainbow

The most distinctive characteristic of tourmaline is undoubtedly its extraordinary color range. This gemstone occurs in more colors and color combinations than virtually any other gemstone, earning it fame as nature’s most colorful crystal. The spectacular diversity results from tourmaline’s complex chemical structure, where subtle changes in composition create dramatic shifts in color.

• Black tourmaline (schorl) is the most common variety, accounting for about 95% of all natural tourmaline. Its dark color comes from high iron content, and while less valuable than other colors, it remains popular in metaphysical communities for its purported protective qualities.
• Pink to red tourmalines (rubellite) range from pale rose to deep crimson. These highly sought-after varieties maintain their color under different lighting conditions (unlike some red stones that can appear brownish), making them particularly valuable. The finest specimens rival rubies in color but typically cost significantly less.
• Green tourmalines (verdelite) span from pale mint to deep forest hues. The most valuable green variety is “chrome tourmaline,” colored by chromium like emeralds, displaying a vivid, rich green similar to fine emeralds but typically with better clarity.
• Blue tourmalines (indicolite) display colors from light sky blue to deep navy. The rarest and most valuable blue variety is “Paraiba tourmaline,” first discovered in Brazil in the 1980s, which has a neon blue to blue-green color due to copper content and can sell for tens of thousands of dollars per carat.
• Watermelon tourmaline features green on the outside and pink on the inside, resembling a watermelon slice when cut perpendicular to the crystal’s length. This striking color zoning occurs because the chemical environment changes as the crystal grows, creating one of nature’s most remarkable color displays.
• Other significant varieties include colorless tourmaline (achroite), yellow to brown (dravite), multi-colored (liddicoatite), and color-change tourmalines that shift hues under different lighting conditions, adding to the gemstone’s mystique and collector appeal.

The value of tourmaline is primarily determined by its color, with Paraiba varieties commanding the highest prices, followed by vivid rubellites, chrome greens, and pure blues. This vast color palette ensures that virtually anyone can find a tourmaline color that speaks to their personal style and preferences.

Major Tourmaline Deposits and Mining Regions

Tourmaline forms in many different geological environments around the world, primarily in granite pegmatites (coarse-grained igneous rocks) and metamorphic rocks like schists. These diverse formation conditions contribute to the wide variety of tourmaline types and colors found globally.

• Brazil stands as the world’s premier source of fine tourmaline, particularly from the states of Minas Gerais and Paraíba. The Paraíba region gained international fame in the late 1980s with the discovery of the vivid electric blue-green copper-bearing tourmalines that now command some of the highest per-carat prices of any colored gemstone.
• Africa has emerged as a major tourmaline producer, with significant deposits in Madagascar, Mozambique, Nigeria, Tanzania, and Namibia. Mozambique has become especially important for high-quality red and pink tourmalines that rival Brazil’s finest specimens, while Nigeria and Mozambique have also yielded copper-bearing tourmalines similar to the Brazilian Paraiba variety.
• The United States has a rich tourmaline mining history, particularly in Maine and California. Maine’s Oxford County produced magnificent pink and green tourmalines beginning in the late 1800s, many of which were purchased by Tiffany & Co. and by Chinese Imperial families. California’s San Diego County was a major source for pink tourmalines highly prized by the Chinese Empress Dowager Cixi.
• Afghanistan and Pakistan produce exceptional rubellite (pink to red tourmaline) and bi-colored stones from the mountainous Nuristan and Kunar provinces. These regions are known for specimens with exceptional clarity and color saturation that command premium prices in the gem market.
• Other significant sources include Sri Lanka (wide variety of colors), Russia’s Ural Mountains (green and pink varieties), and Italy’s Elba Island (which gave its name to elbaite, the most common gem tourmaline species).

Tourmaline’s global distribution ensures a steady supply of this versatile gemstone, though the finest specimens from any location remain rare. The discovery of new varieties, like the Paraiba tourmalines in the 1980s, continues to excite the gem world and demonstrates that even after centuries of mining, tourmaline can still surprise us with new colors and varieties.

Physical Properties and Benefits of Tourmaline

Beyond its visual appeal, tourmaline possesses remarkable physical properties that make it not only a beautiful gemstone but also a practical choice for jewelry and various industrial applications. Its combination of durability and unique characteristics sets it apart from many other gemstones.

• With a hardness of 7 to 7.5 on the Mohs scale, tourmaline is durable enough for everyday wear in all types of jewelry, including rings. It’s resistant to scratching and maintains its polish well over time, though slightly less hard than sapphires (9) or diamonds (10).
• Tourmaline has good toughness (resistance to breaking) despite having one perfect cleavage plane. This means that while it can theoretically break along this plane if struck with significant force, properly cut tourmaline is generally durable enough for daily wear when set in protected settings.
• The most unique physical property of tourmaline is its electrical conductivity. It is both pyroelectric (develops electrical charge when heated) and piezoelectric (develops electrical charge when pressed). This distinctive property has made tourmaline valuable in various scientific instruments like pressure gauges and devices measuring underwater sound waves.
• Tourmaline naturally emits negative ions and far infrared rays when heated, a property utilized in various products from hair styling tools to health-related items. While many health claims aren’t scientifically validated, the physical property of negative ion generation is genuine.
• When crushed into small particles, tourmaline can create a small electrical charge in water that helps bind impurities, making it useful in water purification systems. This application takes advantage of tourmaline’s unique electrical properties in a practical environmental context.

These properties demonstrate that tourmaline is not just a pretty face in the gem world but a mineral with genuine scientific importance and practical applications. Its combination of beauty and functionality has contributed to its growing popularity both in jewelry design and industrial uses.

Tourmaline Metaphysical Properties & Healing Benefits

Throughout history, tourmaline has been associated with numerous metaphysical and healing properties across different cultures. While these beliefs lack scientific verification, they remain an important aspect of tourmaline’s cultural significance and continue to influence why many people are drawn to this colorful gemstone.

• Black tourmaline (schorl) is considered one of the most powerful protective stones in crystal healing traditions. It’s believed to create a shield against negative energies, electromagnetic radiation, and environmental pollutants. Many practitioners use it for “grounding” and protection during meditation or spiritual work.
• Pink and red tourmalines (rubellite) are associated with the heart chakra and are thought to promote love, compassion, and emotional healing. Metaphysical practitioners suggest these stones can help heal past emotional wounds and open one’s capacity for giving and receiving love.
• Green tourmaline is linked to prosperity, growth, and healing. It’s believed to support the immune system and promote physical vitality while fostering a connection to nature. Some crystal healers use it to balance the heart chakra and promote a sense of compassion balanced with healthy boundaries.
• Blue tourmaline (indicolite) corresponds to the throat chakra in many traditions and is said to enhance communication, self-expression, and mental clarity. It’s often recommended for those who need confidence in speaking their truth or communicating difficult emotions.
• Watermelon tourmaline, with its combination of green and pink, is thought to represent the connection between heart and higher consciousness. Its dual nature is believed to help balance opposing energies and integrate dualities within oneself.
• In Ancient Egypt and Medieval Europe, tourmaline was used as a talisman against negative forces and to induce restful sleep. Ancient alchemists believed tourmaline could inspire creativity and was connected to the philosopher’s stone because of its ability to display multiple colors.

These metaphysical associations have contributed significantly to tourmaline’s popularity beyond its aesthetic appeal. Whether or not one believes in crystal healing properties, the cultural and historical significance of these beliefs has cemented tourmaline’s place as one of the most spiritually significant gemstones in numerous traditions worldwide.

Shopping for Tourmaline Jewelry

When shopping for tourmaline jewelry, understanding quality factors and value considerations can help you make an informed purchase that you’ll treasure for years to come. Unlike diamonds with their standardized grading system, tourmaline is evaluated primarily based on color, clarity, cut, and size.

• Color is the most critical factor in determining tourmaline’s value. The most prized colors include Paraiba tourmalines (electric blue to blue-green), vivid rubellites (pink to red) without a brown tinge, chrome tourmalines (emerald-like green), and pure indicolites (medium to dark blue). The most valuable specimens display strong, saturated color with excellent transparency throughout the stone.
• Clarity expectations vary by color variety. Blue and green tourmalines typically have fewer inclusions, so clarity is more important for these varieties. Pink, red, and Paraiba tourmalines naturally contain more inclusions, so slight inclusions don’t impact their value as much. However, inclusions that affect durability or are easily visible to the naked eye will significantly reduce value regardless of color.
• The cut of tourmaline is particularly important due to its pleochroism (showing different colors when viewed from different angles). Expert cutters orient the stone to display the most desirable color face-up. Long rectangular cuts often showcase tourmaline’s natural crystal shape, while oval and round cuts maximize brilliance. Emerald cuts emphasize color and clarity, while cabochons are used for star tourmalines or those with interesting inclusions.
• Size significantly affects tourmaline pricing, with larger stones commanding exponentially higher prices, especially in rare colors like Paraiba. Unlike some gemstones, high-quality tourmaline can be found in larger sizes, with specimens weighing 5 carats or more available in the market, though naturally at premium prices.
• Always ask about treatments, as many tourmalines are heated to improve color. Heat treatment is generally accepted in the industry but should be disclosed. Irradiation and fracture-filling are less common but do occur and should always be disclosed by reputable dealers.

Price ranges vary dramatically based on these factors. Common black tourmaline might cost under $50 per carat, while fine green or pink specimens range from $200-$800 per carat. Premium rubellite can cost $1,000-$3,000 per carat, while exceptional Paraiba tourmalines start at $5,000 per carat and can exceed $30,000 per carat for museum-quality stones.

How to Care for Tourmaline

Tourmaline’s respectable hardness makes it suitable for everyday wear, but proper care will ensure your tourmaline jewelry remains beautiful for generations. Despite its durability, tourmaline can still be damaged by harsh chemicals, extreme heat, or impact if not properly maintained.

• The safest cleaning method for tourmaline jewelry is warm, soapy water (with mild dish soap) and a soft brush, such as a soft toothbrush. Gently scrub the stone, paying attention to the areas around the setting where dirt can accumulate. Rinse thoroughly with clean water and pat dry with a lint-free cloth.
• Avoid ultrasonic cleaners and steam cleaners, as the heat and vibration can potentially damage tourmalines, particularly those with liquid inclusions or fractures. The rapid temperature changes and vibrations could exacerbate existing internal features and potentially cause damage.
• Keep tourmaline jewelry away from harsh chemicals, including chlorine bleach, household cleaners, and swimming pool chemicals. These substances can damage both the stone and its setting over time and potentially dull the polish on your tourmaline.
• Store your tourmaline pieces separately from harder stones like diamonds and sapphires that could scratch them. Ideally, keep each piece in a soft pouch or in a jewelry box with separate compartments to prevent pieces from scratching each other during storage.
• Remove tourmaline jewelry before physical activities like sports, gardening, or household cleaning to prevent potential impacts or exposure to chemicals. Put your jewelry on after applying perfumes, hairsprays, and cosmetics to prevent chemical residue from building up on stones and settings.
• Some tourmaline colors, particularly pink, may fade with prolonged exposure to strong sunlight, so avoid leaving your tourmaline jewelry in direct sunlight for extended periods. This color fading is rare but has been documented in certain specimens.

Following these care guidelines will help preserve your tourmaline jewelry’s beauty and ensure it remains a treasured piece in your collection for many years to come. With proper care, tourmaline’s inherent durability makes it a practical choice for jewelry that can be worn and enjoyed regularly.

Tourmaline as October’s Birthstone

Tourmaline shares the honor of being October’s birthstone alongside opal. It was officially designated as an October birthstone by the American National Association of Jewelers in 1952, making it a relatively recent addition to the traditional birthstone calendar.

• As a birthstone, tourmaline symbolizes balance, strength, and healing. Its vast range of colors offers October-born individuals the freedom to select a hue that resonates with their personal style while still wearing their birthstone.
• The multi-colored nature of tourmaline, particularly watermelon tourmaline, is said to represent the complexity and multi-faceted nature of those born in October. This versatility makes tourmaline especially meaningful as a personalized birthstone choice.
• For those who might find opal (October’s other birthstone) too delicate for everyday wear, tourmaline offers a more durable alternative with a hardness suitable for daily use in all types of jewelry settings, including rings.
• Historically, tourmaline has been associated with artistic inspiration and creative expression, making it a meaningful gift for artistic October-born individuals who might connect with these traditional associations.

For those interested in learning more about tourmaline as October’s birthstone and its relationship with opal, check out our detailed article on October birthstones.

Famous Tourmalines in History

Throughout history, several exceptional tourmaline specimens have achieved fame for their size, quality, or historical significance. These remarkable gems illustrate why tourmaline has captivated collectors, royalty, and museums around the world.

• The Hamlin Necklace, displayed at the Smithsonian National Museum of Natural History, showcases magnificent tourmalines discovered in Maine during the late 19th century. Created by Tiffany & Co., this necklace contains exceptional green and pink tourmalines that represented America’s first major commercial gemstone discovery and helped establish Maine as an important gemstone source.
• The Portuguese Crown Jewels include several significant tourmalines, initially mistaken for rubies when brought from Brazil in the 18th century. When the true identity of these gems was discovered, it helped establish tourmaline as a desirable gemstone in its own right rather than merely a substitute for more precious stones.
• Empress Dowager Cixi of China had a particular affinity for pink tourmaline. In the late 19th and early 20th centuries, she purchased large quantities of pink tourmaline from mines in San Diego County, California. Her passion for these stones drove up prices and spurred mining activity in the region. After her death in 1908, many of these imperial tourmalines were carved into snuff bottles and other decorative items that are now highly prized by collectors.
• The discovery of Paraiba tourmaline in the late 1980s in Brazil’s Paraíba state by miner Heitor Dimas Barbosa revolutionized the gemstone world. After years of digging, Barbosa found electric blue-green tourmalines that commanded unprecedented prices. The “Ethereal Carolina Divine Paraíba” is one of the largest known Paraiba tourmalines, weighing 191.87 carats and valued at millions of dollars.
• The “Steamboat” tourmaline, mined in California in 1972, is one of the most spectacular tourmaline specimens ever found in North America. The large, multi-colored crystal resembles a steamboat and is now housed in the Smithsonian Institution, representing an important piece of American mineralogical heritage.

These famous examples illustrate not only tourmaline’s beauty but also its global appeal and historical significance across different cultures and time periods. They stand as testament to why this remarkably diverse gemstone continues to fascinate collectors, jewelers, and gem enthusiasts around the world, securing its place among the most cherished colored gemstones.

Conclusion

Tourmaline stands as a true marvel in the gemstone world, offering an unparalleled spectrum of colors and remarkable versatility that few other minerals can match. From the protective black schorl to the electric blue Paraiba varieties and the watermelon tourmaline with its captivating color zoning, this gemstone family provides options for every style, occasion, and budget. Its impressive hardness, fascinating electrical properties, and rich historical significance further cement its status as both a beautiful adornment and a stone of scientific interest.

Whether you’re an October baby looking for an alternative birthstone, a collector fascinated by the mineral’s diverse varieties, or simply someone drawn to its vibrant colors, tourmaline offers exceptional beauty and value. With proper care, tourmaline jewelry will maintain its brilliance for generations, making it not just a purchase but an investment in beauty that can become a treasured heirloom. As one of nature’s most colorful creations, tourmaline continues to captivate and inspire with its extraordinary rainbow of possibilities.