<p>An improved detectable tape including a ductile metal foil layer (31) which is enclosed in a sheath (34) of thermoplastic coating which provides sealed edges (36, 38) along the length of the tape. The thermoplastic coating sheath protects the foil from corrosion when the detectable tape is placed underground above a non-metallic body such as plastic pipe. The sealed edge detectable tape can also include a reinforcement layer which provides additional tensile length.</p>
