Alexandarite

Alexandrite is one of the rarest of all colored gemstones available today. More specifically, it is an extremely rare color change variety of chrysoberyl (a cyclosilicate). Despite its name, chrysoberyl, which is an aluminate of beryllium, does not actually belong to the beryl mineral group, but rather, it is classified as its own independent mineral group.The color change phenomenon seen in alexandrite is referred to as the 'alexandrite effect'. The change in color can be observed under certain lighting conditions, typically under daylight and incandescent lighting. It can display emerald green, red, orange and yellow colors depending on which angle the stone is viewed from.