Obsidian is a mystical black stone, or actually volcanic glass meaning it is not a crystal. Its alluring darkness often is accompanied by a silver or golden sheen (or even rainbow coloured) due to tiny bubbles forming when the glass was created.
It is heavily associated with protection and warding, and is thought to reflect evil. One may also find it an excellent tool in divination as it is psychically protective and when flat, can be used as a gazing mirror.
You will receive an intuitively picked crystal from the bowl pictured