We report the results of incoherent scatter radar, total power, and ion line observations of a nighttime sporadic layer centered at 92-km altitude. The height variation of the absolute widths of the ion line yields a layer temperature of 210¿¿5 ¿K and a mean ion mass of 50¿10 amu. This ion mass, when compared with average meteor composition, indicates that the layer is composed totally of metallic ions.