Quite simply: the shipbuilders supplied the White Star Line with the metal to build the Titanic – Harland and Wolff, Belfast. As to who it was that supplied H&W … “The steel used to build Titanic was not the first class steel we would associate with shipbuilding today. The time of mass production was just beginning, and materials were not that easy to come by. It was not cut costing, [sic] it was simply of the time and using what technology was available then. Materials were bought from several sources to meet supply. Steel came from Scotland, Ireland and England.” Media & Aviation ‘Expert’ [??] Julian Bray. See the rest of this interesting article concerning the vessel’s construction, at: http://julianbrayrecessionbuster07944217… (I think he meant to say “It was not cost-cutting …”) Hope this is of central interest.