Aquamarine is a beryl like emeralds and morganite sometimes called pink emeralds. Unlike emeralds, aquamarine is generally flawless. Its beautiful blue colour has broad appeal - the deeper the colour, the more valuable. However, it is correctly, a blue-green gemstone although any hint of green would generally lower its value. In centuries past, the green-blue varieties were preferred and therefore more costly unlike today.

The name is derived from Latin aqua for water and mare for sea. So it is not surprising that sailors long ago used this gemstone to keep them safe, prevent seasickness and help them sleep. A delightful mariner's tale claims the aquamarine to be from the mermaid's treasure chest. According to old beliefs, aquamarine could soothe and cure - it was once considered a poison antidote. A woman who wore aquamarine would be blessed with a happy marriage due to the stone's supposed calming influence on relationships. Lo and behold, it is the nineteenth wedding anniversary gemstone.

Aquamarine is found in many places but most of what is available today comes from Brazil.

References
Wikipedia : Aquamarine
International Colored Gemstone Association : Aquamarine
American Gem Trade Association : Aquamarine