Black amethyst is a darker natural version of amethyst due to hematite inclusions and a higher iron content found inside it's crystalline matrix.
Amethyst has one of the strongest powers to rid your home of negative influences. 
Place an amethyst cluster in the south corner of any room in your home to allow life force energy to flow through your home.
Amethyst is a natural stress reliever that also encourages inner strength, spirituality and intuition. It attracts positive energy while ridding the body or your home of negative energy. Promotes sobriety, helps break addictions; encourages spiritual awakening and peace; transformation and meditation; calms, balances, and clears aura.