Eldorado Mining and Refining Limited

The Eldorado Mining and Refining Limited company was originally organized in 1927 as Eldorado Gold Mines Limited to develop a gold mine in Manitoba. Its president Gilbert LaBine later found radioactive deposits at Great Bear Lake, Northwest Territories in 1930, which led to the development of the Eldorado Mine at Port Radium. They built a state-of-the-art refinery in Port Hope, Ontario in 1933. Radium production took place between 1933 and 1940 when World War II closed European markets for radium material. The other byproduct of the company was silver, copper, and uranium salts. Uranium was useless until scientists realized the enormous energy potential of the uranium atom. The company reopened the mine at Port Radium in 1942 to supply the United States military with uranium products. The Canadian Government took over the company by purchasing share control in 1943, and in early 1944 the name was changed to Eldorado Mining and Refining Limited.

In mid-1943 the District Engineer of the Manhattan Engineer District, Lt-Col Kenneth Nichols had several queries from Canada relating to contracts Canadian firms Eldorado Gold Mines and Consolidated Mining and Smelting (CMS) had for the secret atomic bomb project; CMS or Cominco was building a heavy water plant at Trail, British Columbia and Eldorado was mining and processing uranium ore. He phoned a C. D. Howe in Ottawa and arranged to travel on the overnight train to Ottawa and see Howe the next day (June 14). On arriving at the address given Nichols was surprised to find that Howe was the minister of munitions and supply, and found him most friendly. Howe was told about the Manhattan Project, and Nichols was told that Eldorado was now a Crown company.

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