Four stones are considered to be in the Beryl family. They are:
Morganite
Heliodor
Goshenite
and the March birthstone: AQUAMARINE.
Legend has it that aquamarine originally came from a mermaids jewely box (Latin aqua maris meanssea water). It is said to bring pure love. By turning darker or lighter, the stone indicates what is true and false. When it becomes almost white, it is sad to warn against false friends.