When Meghan Markle flashed an aquamarine ring from the passenger seat of a matching blue Jaguar being driven by new husband Prince Harry to their wedding reception, baby-blue gems zoomed to the top of the rock charts.
Gems should be viewed under the right optical conditions. Put the stone against a sheet of white paper either in natural light or under fluorescent tube lighting. To the naked eye, an aquamarine will often have a slight greenish cast to it, which a blue topaz totally lacks. Another test: Aquamarines are pleochroic, which means they throw off different colours when viewed at different angles.
There is a cool exception, though: cat’s-eye aquamarines, which are a rare anomaly of nature. Here, the flaw usually takes the form of parallel microscopic tubes inside the gem that are either hollow or filled with liquid. A good lapidary will cut the gem to showcase the flaw so that it has a satiny, striated cat’s-eye effect whenever it catches the light.Aquamarines are pretty tough, but you should make sure they’re sturdily set, especially in wear-everywhere rings.