Iron oxides and iron hydroxides are main components of the rust formed on the surface of ancient iron implements. These iron compounds are generally classified by their mineral components such as magnetite (Fe₃O₄), goethite (Á8-FeOOH) and lepidocrocite (Ãœ3-FeOOH). Akaganeite (beta-FeOOH) was found in rust samples taken from iron implements excavated from several ancient tombs; the formation mechanism of this rare mineral is discussed. The kind of rust found seems to be a good indicator of burial conditions. -- AATA