This genuine Evil Eye bead is made of genuine blue opal and sterling silver around the bead; size of the bead is 10mm. The eye comes with a fine 18 inch sterling silver chain. If you prefer, you can have this necklace with a 16" or 20" at no extra charge. The Evil Eye also called the invidious eye and the envious eye, is that a person can harm you, your children, your livestock, or your fruit trees, by "looking at them" with envy and praising them. To keep yourself safe from harm, negative energies, emitted by brain, use this symbol either in a necklace or in a bracelet. It is a combination of a jewel and a strong protective symbol. Tradition states that the wearer is protected from envious stares, receives protection from all evil, and receives good luck.