Sky Metal, also called electropartes (electroparts) or “the blue metal,” is pristine blue metal fallen from the sky: satellite electroparts. The first pieces crashed near the Refinery & Dam.
It is not scrap but reality-building nodes: matter from which armor is forged, nanobots are assembled and the gravity train is built that pierces the way to the sphere of the Master. The nanobots of the frayed edge of reality come out of the same matter.