A somewhat belated note on the June birthstone you’re least likely to casually come across.
It’s an unusual and pretty rare stone called Alexandrite. Alexandrite is a variety of chrysoberyl, a more common form of chrysoberyl is cat’s eye.
Chrysoberyl are oxide minerals and despite the name, bear no relation to beryl gemstones like aquamarine and emerald.
What’s amazing is that alexandrite changes color depending on the type of lighting it is viewed in. This happens when chromium atoms replace some of the aluminum atoms in the chrysoberyl structure.