Natural Pink Tourmaline Smooth Polished Tear Drops 15 Beads & Sizes 5mm to 9mm approx. Contact us to buy less length. Tourmaline (tur-mah-Leen) is a crystal 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 comes in a wide variety of colors.