An olive stone, also known as an olive pit, is the hard seed found inside an olive. It is typically oval-shaped and can vary in size depending on the type of olive. Olive stones are not edible and are usually discarded after the fruit is consumed or processed. In addition to being a byproduct of olive consumption, olive stones have various uses. They can be ground into a powder for biofuel or used in cosmetics and food products as a natural exfoliant. Some people also use them for gardening, as they can help improve soil drainage.