 In 1864, Edwin J. Hulbert discovered a copper-bearing section of what became known as the Calumet Conglomerate of Precambrian age.The find was in Houghton County, Michigan, between the rich Cliff mine to the northeast, and the copper mines of Portage Lake to the southwest, but a long way from either.Hulbert formed the Hulbert Mining Company in 1864 to acquire the land rights, before creating the Calumet Company in 1865, with Boston investors.