Onyx is a type of chalcedony and is used for centering and aligning you to your highest powers and purpose. An excellent stone for grief, it is also used to enhance self-control, to promote good decision making, and to encourage happiness and good fortune. It helps you to absorb all the good energies that the universe provides you.
For intuitives and psychics, it is an excellent stone for creating clear communication by cleansing and blockages or “whisper spots” where you cannot seem to hear messages clearly. Good for balancing yin and yang energy.
Physically, people use it for disorders of the feet, soft tissues, and bone marrow.