Canada is a leading producer of nickel and the mining of this metal has contributed significantly to the nation's economy. The industry is closely tied to the Sudbury Basin whose mines have produced the greater part of the metal in this country. Nickel, in association with other metals, was discovered here in 1883 and mining for copper began shortly thereafter; but it was not until the 1890s with the development of nickel-steel alloys that the ore was mined primarily for its nickel. The Creighton mine, which opened in 1900, became the largest nickel mine in the world.