I use black castor oil in my Hair Growth Oil. Made from the seeds of the tropical plant Ricinus communis. The seed (not actually a bean) has an astonishing 40-60% oil which is rich in triglycerides including Omega-9 fatty acid and is one of the only sources of ricinoleic acid. It also has a second name, Palm of Christ due to its use as a healing salve for wounds and illness. Often Castor is thought to be animal derived because it actually replaced an animal product made from beaver used in perfumery. Castor Oil it is 100% vegetable derived.
Castor Oil has a long and varied list of uses including for hair growth and hair health. Please know, I can find no scientific evidence that Black Castor Oil will grow hair. Still, it is used all over the world for just that.
We do know that ricinoleic acid in Castor Oil can help other substances penetrate further into the skin, helps prevent water loss and may act as an antifungal. It can also act as a analgesic and anti-inflammatory.
In Jamaica, special Black Castor oil is made by roasting the beans to extract the oil. The color comes from the process of roasting. And the ashes of the firing give Black Castor Oil different qualities. The benfits of Black Castor Oil are gained by the roasting. This is similar to the benefits African Black Soap get from being made over an open fire and also the usefulness of Activated Charcoal products.