Description Marvelous, multi-color tourmaline beads! Dimensions:  142 beads ranging in size from 7 x 8 mm to 9 x 11 mm Weight:  140 grams TOURMALINE, a boron aluminum silicate, is perhaps the most fascinating of all gems. The diversity of its colors, the complexity of its composition, and the wonders of its physical properties are unmatched by any other gemstone. It comes in virtually every color, sometimes with several in the same crystal. The many varieties of tourmaline have been categorized into 6 major species: uvite, schorl, elbaite, liddicoatite, buergerite and dravite. Generally, only the elbaite and liddicoatite, which contain lithium, occur in rainbow colors, including the popular red-green combination aptly nicknamed “watermelon”. Tourmaline exhibits both pyroelectric (static electric) and piezoelectric properties. The latter makes it useful as a frequency stabilizer, a property it shares with quartz. As its powerful healing energies continue to unfold, tourmaline is emerging as one of the most important healing stones of the new age. Major deposits have been found in Brazil, Afghanistan, California and Maine, and Elba, Italy