also saw the opening of an ore improvement plant in 1958. This plant separated the iron ore into coarse and fine products through a gravity screening method. This allowed for the coarser ore to be bought at a premium price because it was more uniform in size and grade. It resulted in a more efficient blast furnace operation at the steel mills. The Hogarth Open Pit was in operation until 1978 when it closed due to an economic drop in iron ore. "Operation Up and Over" Dredge Move Once dredging was completed in the Hogarth Mine pit, the challenge then became moving the two dredges into the final ore zone that was to be mined by Steep Rock Iron Mines. The plan that was settled upon was an overland move of the dredges from Hogarth to the "G" Ore Zone because it was the most economic. The dredges "Steep Rock" and "Marmion" were prepped by adding continuous tracks to the base of the dredges. The dredges were then attached to bulldozers and other heavy machinery by long metal cables. The dredges began their overland move in March 1954. The distance was two miles and contained a vertical lift of 240 ft. There were 8% grades and one sharp corner that could cause delays if not planned properly. The move took two weeks to complete and the dredges arrived at the "G" ore zone without any problems. "G" Ore Zone (Roberts Mine) The final ore zone to be mined by Steep Rock Iron Mines was the "G" ore zone-renamed the Roberts Mine after Hugh Roberts, geologist of Steep Rock Iron Mines- which was situated in the middle of the western portion of the Steep Rock Range, midway between the Hogarth and Errington orebodies. The dredging of the "G" ore zone started in 1954 after the two dredges "Steep Rock" and "Marmion" were moved. The dredging continued until 1962. The mine was renamed Roberts Mine in 1961. The first load of iron ore was shipped from the mine in 1964. During this time, Steep Rock Iron Mines entered into the modern mining equipment and methods. The first 100-ton electric wheel haulage trucks were used at Steep Rock along with large 10- and 11- cubic-yard shovels. In addition to the equipment, many of the advances in slope stability and open pit design that were widely used in Canadian mining were developed at Steep