Diameter: 55.000 cm
This is part of a revolutionary new domestic appliance that probably helped to change life in an Iron Age household. It is the top part of an rotatory quern used to grind grains of wheat, barley or rye into flour to make bread and other foods. A rotatory quern consisted of two quern stones, one on top of the other. The lower stone did not move; the top stone was turned around a wooden axle that passed up through the hole in its centre.
The idea for a rotatory quern arrived in Britain in the middle of the Iron Age (about 400-300 BC) and quickly spread. It probably significantly shortened the time needed to make the same amount of flour, or allowed far more flour to be made than before.