tourmaline(Tourmaline ( /ˈtʊərməlɪn/, -/iːn/ TOOR-mə-lin, -leen) is a crystalline boron silicate mineral compounded with elements such as aluminium, iron, magnesium, sodium, lithium, or potassium. Tourmaline is classified as a semi-precious stone and the gemstone can be found in a wide variety of colors. wikipedia.org)
