The name tourmaline derives from the Singhalese word "turamali" meaning gemstone. Known as the "rainbow gemstone," tourmaline comes in every color of the rainbow - and most tourmaline gemstones are multi-colored. Gem cutters focus on bringing out the deepest color when cutting tourmaline. Still, when viewed from different angles, a tourmaline may exhibit different colors.
Tourmaline is reputed to have a powerful positive influence on love and friendship. Though available in any color, in multi-colored samples and as dark as opaque black, shades of pink and green seem to be the most favorable for jewelry design.
Primarily composed of sodium and boro-silicate hydroxide, tourmaline has a Mohs hardness rating of 7 to 7.5, making it a great gemstone for jewelry.