Most people do not realise that onyx thumb stones is part of the black agate family. If onyx is not a glassy black, black with a bit or white and/or brown and / or red, then they are banded calcite from Pakistan!
Like all of its crystal family members, it brings you strength and courage, and will help to lessen fear and stress, however it uniquely aids you to connect to the planet and to encourage you to shamanically accept your “dark” side. It reduces sensitivity for people working with those who have mental health issues.
As these onyx thumb stones are slightly undersized, their price is reduced.