Emerald is the birthstone for the month of May, representing the star signs of Taurus (May 1-20) and Gemini (May 21-31). Emeralds vary in shades of green and are graded based on color, clarity, cut, and carat weight, with color being the most important factor in determining quality and value. Emeralds have been mined since ancient times in Egypt and India and are currently most heavily produced in Colombia, which mines 50-95% of the world's emeralds annually. Emeralds symbolize loyalty, new beginnings, peace, and security, making them a meaningful gemstone for both jewelry and gifts.