Gristmills

Gristmills are facilities that grind grain into flour or meal for human consumption. The term grist refers to grain that is ground; the product may be fine flour, coarse meal, or bran-rich sorts depending on the milling process. Gristmills have been powered by water, wind, or, in modern times, electricity.

Traditional stone gristmills use a pair of millstones. Grain is fed from a hopper into the gap between a fixed bedstone and a rotating runner stone. The runner stone is driven by a drive mechanism linked to a water wheel, turbine, or electric motor. As the stones turn, grain is ground and the meal exits through a chute, while bran and germ may be sifted out or retained for different products. The gap between stones, called the clearance, affects grind size. Ancillary equipment such as the shoe, spout, and sieve manage feed and collection.

Grain grinding with stone mills appears in ancient times and became widespread in classical antiquity and the medieval period. Water-powered mills were common along rivers; windmills rose in various regions during the Middle Ages. Mills often served as focal points of communities, sometimes providing employment and local economies.

Today, stone-ground gristmills operate as heritage sites or artisanal producers, preserving traditional methods. Most modern flour production uses roller mills and complex milling lines driven by electricity, but artisan mills may still rely on stone grinding to produce whole-grain flours with retained bran and germ. In some regions, restored mills function for demonstrations or tourism.