Opal is recognized as the queen of all
gemstones and is one of the oldest gemstones
since ancient civilization. The term Opal is
thought to be taken from the Sanskrit Upala,
which means "precious stone," and after the
Greek derivative "Opallios," which means to
see a change of color. The stone can be found
in gray, blue, pink, yellow, and brown colors
and looks transparent to opaque in
appearance.