Carnauba wax is extracted from the leaves of a species of palm tree native to Brazil. The thin wax film on the leaves is water-repellent and protects them from drying in hot sun. Found in extreme conditions, carnauba is the hardest known natural wax. Carnauba wax is used to reinforce oiled floor surfaces. The wax will join oil in filling the surface of wood pores, creating a protective film against mechanical damage, dirt and water. A floor treated with carnauba wax will be water-vapour permeable, which is important for maintaining the natural properties of wood flooring.