It was not until 1937, with the threat of war in Europe and the emergence of a profitable market for Canadian iron ore, that the Helen Mine was reopened. A sintering plant was constructed on the northern bank of the Magpie River, two miles west of the mine. It was used to treat the siderite ore before it was shipped to the blast furnaces at Algoma Steel in Sault Ste. Marie. The plant became the centre for a small community called Sinterville, composed of workers and their families.