What is castor oil used for? For nourishing hair, skin and brows. Castor oil benefits for skin and hair are plentiful because of its nourishing properties. We used a traditional African method of pressing roasted castor beans to create a naturally occurring ash. Rich in omegas, minerals, and ricinoleic fatty acids, Black Castor Oil helps hydrate dry skin and nourish hair. Ideal for all skin types.