Blue Onyx is a variety of Onyx, which is a type of Chalcedony, that crystallizes in the form of blue, white, and brown-banded masses.
Blue Onyx is a stone of the throat chakra that opens your communicative skills to not only yourself but also the world around you. Try placing a piece directly over your throat chakra during or after your meditation, or even carrying a piece with you throughout your day! You may initially notice a sense of overall softening of your attitude and reactions to others. This inner reflection teaches you that you are only able to treat others how you treat yourself.