Onyx gemstone is often not even as the name implies: Black! Instead it is actually named for the multi colored layers in it. It can have a black base and white up top commonly. But it can be brown or red and white as well. Onyx belongs to the Quartz family and Black Onyx is really the most inexpensive of the blacks stones because of the abundance of it. Onyx is most know to rid negativity and separate bothersome relationships as well. The black colored stone aids in relaxing and can increase strength. It is the mystical birthstone of December and is associated with Saturn and Earth.