Tourmaline (/ˈtʊərməlɪn, -ˌlin/ TOOR-mə-lin, -leen) is a crystalline silicate mineral group in which boron is composed of elements such as aluminum, iron, magnesium, sodium, lithium, or potassium. Tourmaline is a gemstone and can be found in a variety of colors. The term comes from the Sinhala “tōramalli”, which refers to carnelian gemstones.