Tourmaline is a crystalline silicate mineral containing boron and other elements like aluminum, iron, magnesium, sodium, lithium, or potassium. It displays an array of colors such as black, deep brown, blue, green, yellow, pink, red, orange, purple, brown, and colorless depending upon the chemical composition. Color zoning is also seen in some stones. It is durable and resistant to scratches and hence useful for making jewelry. It is believed to possess the properties of stress reduction, detoxification, and promoting emotional balance.