Indeed, there were various indications of a non-metallic surface: a flat, low frequency spectrum similar to that of carbonaceous chondrites and C-type asteroids and not at all like that of metallic meteorites, a low radar albedo unlike the high albedos of strongly metallic asteroids like 16 Psyche, evidence of hydrated materials on its surface, abundant silicates, and a thicker regolith than most asteroids.