Emerald is a variety of the beryl mineral that is colored green due to trace amounts of chromium and sometimes vanadium. It has a hardness of 7.5-8 on the Mohs scale. Emerald is the birthstone for March, April, May, June, September, October, and the zodiac stone for Aries, Taurus, Gemini, and Libra. Emerald is associated with love, serenity, joy, intelligence, cleansing, clear vision, intuition, truth, clairvoyance, memory, communication, and has healing properties such as stimulating mental capacity, imparting reason and wisdom, ensuring physical and mental balance, and enhancing psychic abilities.