Millstone

Millstones or mill stones are stones used in grist mills, for grinding wheat or other grains.

Millstones come in pairs. The base or bedstone is stationary. Above the bedstone is the turning runner stone which actually does the grinding. The runner stone spins above the stationary bedstone creating the "scissoring" or grinding action of the stones. A runner stone is generally slightly concave, while the bedstone is slightly convex. This helps to channel the ground flour to the outer edges of the stones where it can be gathered up.

The runner stone is supported by a cross-shaped metal piece (rind or rynd) fixed to a "mace head" topping the main shaft or spindle leading to the driving mechanism of the mill (wind, water (including tide) or other means).

History

Neolithic and Upper Paleolithic people used millstones to grind grains, nuts, rhizomes and other vegetable food products for consumption. These implements are often called grinding stones. They used either staddle stones or rotary querns turned by hand. Such devices were also used to grind pigments and metal ores prior to smelting.