Coins from 1946-1952 weigh 4.54 grams, with a diameter of 21.3 mm (opposite corners) 20.9 mm (opposite sides) and a thickness of 1.7 mm. They have a composition of .99 nickel.
Since Canada was the largest single producer of nickel in the world, a coin was issued in 1951 to commemorate the isolation and naming of the element nickel. The design of a nickel refinery was picked by the Mint from entries submitted in an open competition. Near the end of 1951, the use of nickel was suspended due to the Korean War. In its place, steel coins were struck.