Who makes refining and products for AI data centers

Between the mine and the busbar sit smelting, refining and fabrication. Smelters turn concentrate into blister copper, refineries produce the cathode that is the traded form, and fabricators draw, roll and extrude that cathode into wire, cable, sheet, strip, tube and machined parts. Each step is a separate industry with its own capacity constraints. Smelting and refining capacity is heavily concentrated in China, which is a different exposure from mining concentration and is the one most often missed — a diversified mine supply that must pass through a concentrated refining step is not diversified where it matters. Refining margins are set by treatment charges negotiated between miners and smelters, and those charges have swung sharply when concentrate supply and smelter capacity have moved out of balance. Fabrication is where this part touches the data center directly. The same fabricators appear elsewhere in this catalog making cable, tube and busbar, and their constraint is usually capacity in a specific product form rather than copper availability — a shortage of large-conductor cable is a fabrication and lead-time problem, not a metal one. Scrap matters too: recycled copper supplies a substantial share of refined output and responds to price much faster than mining does. What to look for is which step a company occupies, since the economics differ completely across them.