The archaeomagnetic dating technique that is based on the principle that the direction and intensity of the earth’s magnetic field vary through time. When clayey sediment containing magnetic particles (such as in the walls and floor of a hearth) is heated to a sufficient temperature, the magnetic particles in the clay assume and retain the direction of the current magnetic field. The archaeomagnetic dating method measures the magnetic field as preserved in fired clay and compares it to a known record of the changes in the magnetic field through time.