Any place where a pit was dug and a fire built, sometimes identified by charcoal, baked earth, ash, discoloration, or an outline of stones or clay footing. The site of an open domestic fire might have served as kiln or oven. Hearths often appear in one layer of soil after another as an archaeologist digs down through a site, and they are an indication of a succession of camps or habitations. Charcoal from a hearth can be dated by the radiocarbon method. Baked clay in a hearth can be dated by the palaeomagnetic method. Burnt earthen rims may provide oxidized material for archaeomagnetic dating. The hearth is often centrally located and has a variety of shapes and sizes.