Rustic hand-forged thin iron band. Risk of rust and finger discoloration. If this is an issue, recommend stainless steel oxidized or iron/silver. Coated with Everbrite Protectaclear to prevent rust/finger discoloration. Iron is an element that is the principle component in steel. Steel is an alloy of iron and carbon. These rings are made from A36 steel, aka “mild steel” aka low carbon steel, which is 98% iron by composition. If someone requests it, could also be made from 1018 steel (99% iron by composition) but will have no effect on the appearance.