Tourmaline

Tourmaline is known for its wide range of colors, including pink, red (rubellite), green (verdelite), blue (indicolite), and multicolored varieties (watermelon tourmaline). Some stones can even show multiple colors in one specimen. It belongs to the hexagonal crystal system, often forming elongated, prismatic crystals. Many tourmalines exhibit pleochroism, showing different colors when viewed from different angles. Tourmaline can become electrically charged when heated or rubbed, a property known as pyroelectricity and piezoelectricity. Due to its beautiful colors and interesting inclusions, tourmaline is often cut into cabochons. It has a Mohs hardness of 7 to 7.5, making it durable enough for various types of jewelry.