by the lack of the letter "P" under Queen Elizabeth's portrait, and for their non-magnetic quality. Starting with the 1942 tombac coins, the nickel was made dodecagonal, presumably to help distinguish it from the cent after it tarnished in circulation. Tombac was removed from the nickel in 1944 (to be replaced by steel, as noted during the Korean war) but the coins in Tombac, steel, or 99.9% nickel all remained twelve-sided until 1963. All of these coins were lighter than the US version, which is minted to be as close as possible to five grams. Canadian 99.9% nickel five-cent coins are nearly 0.5 gram lighter than this, and its present steel coins are a full gram lighter than US "nickels." 1921 five-cent coin Five-cent coins dated 1921 are among the rarest and most collectible Canadian circulation coins, known as "The Prince of Canadian Coins." Estimates of the number of specimens known range between 400 and 480. In May 1921 the government of Canada passed an act authorizing the change to the larger nickel coin, and subsequently the majority of the 1921 mint run was melted down. The coin believed to be the finest known specimen (PCGS MS-67) sold for at auction in January 2010. It was then sold by the Canadian Numismatic Company for $160,000 to a private collector in early 2012. Types and specifications Commemorative nickels Although not strictly a commemorative, the "Victory nickel", struck from 1943 to 1945, was the first non-standard circulating Canadian coin other than commemorative dollars; the reverse features a flaming torch and a large V that stands for both Victory and the coin's denomination. The rim denticles were replaced by the phrase "We win when we work willingly" in Morse Code. This design was re-used in 2005 to commemorate the 60th anniversary of V-E Day. Almost uniquely in the history of Canadian coinage, the reverse was engraved to scale by Thomas Shingles; most coin designs are engraved at a much larger scale and reduced with a pantograph. In 1951, a special commemorative five-cent piece depicting a nickel refinery was struck to celebrate the 200th anniversary of the metal's initial discovery by Swedish chemist Axel F. Cronstedt. Due to the onset of the Korean War, production of this commemorative was halted to preserve nickel for the war effort, resulting in a second non-commemorative 1951 "nickel" made of plated steel. In 1967, all the circulating coins