The chief use of this metal, which is known in the ingot form as "spelter," is in galvanising sheet iron. Its great advantage is, that while it quickly tarnishes or oxidises, the film so formed is indissoluble and forms a protective coating for the metal beneath.

For rolling into sheets it is essential that the metal should be pure, and also whilst passing through the rolls that its temperature should be between 200° and 250° F.