Among the many steps in the traditional manufacturing of a Laguiole knife, heat treatment is particularly important. It allows the blades to acquire the necessary toughness. The steel goes through two types of thermal variations. Quenching first, rapid heating and cooling which hardens the metal until it becomes brittle. After passing through an oven at 1,652°F (900°C), the pieces are soaked in a cold oil bath. Then the tempering, slower heating and cooling, which gives flexibility to the blade and allows its machining.