In 1937, the beaver motif was introduced for the five cents after being first considered for the ten cent coin. A dot appears after the date on all 1937 coins. This was done to balance the design.
In 1942, because of the World War, the five cents was made with a brass alloy called "tombac" to conserve nickel. It was made with 12 sides to avoid confusion with the cents.
The torch and the "V" design on the 1944-1945 coinage was to promote the war effort. It was made mainly of steel due to the demands for copper and zinc during the war.
After the war ended, the five cents piece was once again made of nickel and because the 12 sided shape were so popular, it was retained.
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.