The Gemstone Emerald is the green variety of the mineral Beryl. Emerald is both the May birthstone and the Zodiac stone for the constellation of Cancer. Emerald gemstones are associated with patience, understanding, and foresight.
Even artificial emeralds often contain flaws, however, as the process of growing artificial emeralds mimics the way nature does it (slow crystal growth from a molten mix).
Nearly all emeralds, even many "natural" stones, have been treated to improve clarity, generally by immersing them in oil. For gemstones, a green colored oil is sometimes used, "improving" the color as well. Unfortunately, this oil may evaporate over the years, making flaws appear where none were visible at the time of purchase. A high-grade mineral oil may be used to improve the appearance again.
For natural emerald specimens, see our Emerald Specimens pages.