Stone and Muller

A stone and muller is a simple hand-operated tool for mixing and grinding paint, made of two flat stone surfaces that are rubbed together to work pigment into a paste, unlike a mortar and pestle, which uses a bowl and a stick. It was in common use among artists and tradesmen from the late eighteenth through the nineteenth century, and largely fell out of use after the mechanical paint mill was introduced in the mid-nineteenth century, surviving afterward mainly for grinding small quantities of pigment by hand.