Used as a stone of strength and protection since ancient times, sardonyx is associated with courage, happiness and clear communication. It brings lasting happiness and stability to marriage and partnerships.
If you're clever, versatile, highly verbal and have an optimistic disposition, those traits may be heightened when you use black and white-banded sardonyx. Or, you can use it to help you control one of those traits if it's working against you. Some believe that placing sardonyx at each corner of a house will protect against evil.