Millstone

Stones used in gristmills, for grinding wheat or other grains

Millstones or mill stones are stones used in gristmills, used for triturating, crushing or, more specifically, grinding wheat or other grains. They are sometimes referred to as grindstones or grinding stones. Millstones come in pairs: a stationary base with a convex rim known as the bedstone (or nether millstone) and a concave-rimmed runner stone that rotates.

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