RA Cosmetics 100% Liquid Black Soap 8 ozBlack soap has traditionally been used in Ghana and Nigeria to treat acne, oily skin and blemishes. This may be a result of the potash that gives the soap its black color. Raw black soap is generally made with plantain skins, a good source of Vitamins A and E as well as iron. Vitamin E is an antioxidant that helps your skin retain its health and moisture. Vitamin A keeps your skin young and fights wrinkles and spots. Iron may also strengthen your skin and hair.