Amethyst NecklaceAmethyst turns purple when trace amounts of iron are incorporated into growing quartz crystal. After crystallization, gamma rays, irradiate the iron to produce the purple color. The darkest color of the amethyst forms when the largest amount of iron is incorporated in the growing crystal. This necklace is 18" with an extender, and a black wax cord. The natural gemstone pendant is 1' long. (#4425) Item in stock unless noted above.