None of the M-type asteroids have bulk densities consistent with a pure iron-nickel core. If these objects are porous (aka rubble-piles), then that interpretation may still hold; however, the consensus is that this is unlikely for Psyche, because of its large size. Given the spectral evidence of silicates on most M-type asteroids, the consensus interpretation for most of these larger asteroids is that they are composed of lower density meteorite analogs (e.g. enstatite chondrites, metal-rich carbonaceous chondrites, mesosiderites), and in some cases may also be rubble piles.
