This process is named after the hand-held instrument that originally was used to make this type of finish, the bush-hammer, which use is dated back to the Middle Age. This process is performed by shocking the surface with the typical hammer with pyramidal tips . It can be graduated in three different variants: fine, medium and coarse, which correspond to progressively higher degrees of roughness and anti-slipperiness, slightly lightening the overall natural coloration. This type of treatment gives the surface of Trachyte a rough and carved effect, making the surface similar to that of the raw material by enhancing its texture. A grazing light well emphasizes the strong contrasts of chiaroscuro created on the surface and highlights its shades and colors. Given the anti-slippery properties resulting from this treatment, bush-hammering becomes particularly suitable for outdoor areas but also for fountains and sinks due to its natural appearance recalling the ancient stone.