Emeralds are the ideal green, and they make a striking addition to any piece of jewelry. High-quality emeralds are cut to maximize the intensity of their color, not their size. At Blue Nile, you'll find our hand-selected emerald jewelry has rich, saturated color, pure hues, and good translucency. Emerald is the traditional birthstone for the month of May. Do not clean your emerald with an ultrasonic cleaner.