Natural Pink Tourmaline Faceted Roundel Beads Strand Length is 8 Inches & Sizes 2mm to 5mm 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.