Tourmaline is one of the most colorful and captivating gemstones in the world. Its vibrant hues span almost every color of the rainbow, making it a favorite among collectors and gem enthusiasts. Beyond its stunning appearance, Tourmaline is known for its fascinating properties and unique characteristics.
Here are 15 intriguing facts about this remarkable mineral:
1. A Unique Shape

Tourmaline is the only mineral that forms in three-sided prisms. This distinctive feature sets it apart from all other minerals.
2. The ‘Cat’s Eye’ Effect
Cat’s Eye Tourmaline gets its name from the way it reflects light, resembling a cat’s eye. This optical phenomenon is known as “chatoyancy,” derived from the French phrase ‘oeil de chat,’ meaning “eye of the cat.”
3. High-Energy Black Tourmaline

Black Tourmaline, also called Schorl, is known for its strong positive energy. It’s the most pyroelectric form of Tourmaline, meaning it can generate a temporary voltage when heated or cooled.
4. Watermelon Tourmaline

As its name suggests, Watermelon Tourmaline displays two distinct colors: a green outer layer and a pink inner core, mimicking the appearance of the fruit. The name may not be the most imaginative, but the gem itself is a true marvel.
5. Misidentified for Centuries

Until the 1800s, Tourmaline was not recognized as a distinct mineral. It was often mistaken for other gemstones, such as emeralds and topaz. Legend has it that the Spaniard who first found Tourmaline off the coast of Italy thought he had discovered an emerald.
6. A Gemstone with History

Tourmaline was first discovered in Maine in 1820, the same year Maine became the 23rd state in the United States.
7. A Rainbow Legend

According to legend, Tourmaline traveled through a rainbow on its way to Earth, which is why it comes in so many different colors.
8. Valued by Weight
The value of Tourmaline is often determined by its carat weight, with larger stones being more valuable.
9. How It Forms

Tourmaline forms in host rocks like granite or schist, within pegmatites—voids that fill with hot, mineral-rich liquids. As these liquids cool, they crystallize into Tourmaline.
10. Color Zoning: A Unique Trait

While color zoning in gemstones is usually undesirable, it’s a prized feature in Tourmaline. Bicolor or zoned Tourmaline crystals are highly sought after by jewelers and collectors.
11. A Spectrum of Colors
Tourmaline comes in more color variations than any other gemstone, offering an unparalleled range of shades.
12. Abundant Schorl

Schorl, or Black Tourmaline, makes up about 90% of all Tourmaline found in nature.
13. Practical Applications
Schorl is not only admired for its beauty but is also used in practical applications like pressure gauges and water purification systems.