Here's some information from the Royal Canadian Mint, where all our money is made:
Pennies: (1 cent.) Prior to 1997 the one-cent coin was 98% copper, 1.75% zinc and 0.25% other metals. From 1997 until 2000, the coin was made of copper-plated zinc. Since 2000 pennies have been 94% steel, 1.5% nickel, 4.5% copper plating. Nickels: (5 cent.) Up until 1922, Canada's five cent coins were made mostly of silver (92.5 %, or sterling silver until 1920, then 80 %, or fine silver). In 1918 and 1919, the five cent coin required more than one third the silver allotted for coining. The composition of the five cent coin was changed to 100% nickel in 1922, saving the Canadian government about $150,000 per year. Between 1942 and 1955 various materials was used include chromium plated steel and tombac. From 1982 until 2000 it was made of cupro-nickel (75% copper and 25% nickel), after 2000 its composition was changed to nickel-plated steel (94.5% steel, 3.5% copper, 2% nickel). Dimes: With the price of silver rising in 1968, people began hoarding ten cent coins as their composition still included 50% silver. Production of nickel coins was authorized in August of that year, but the Royal Canadian Mint could not meet the demand created by the combination of hoarding and circulation requirements. The Canadian Government was required, for the first time since the opening of the Mint, to fill part of the demand elsewhere. Eighty five million ten cent coins were ordered from the Philadelphia branch of the U.S. mint. The ten-cent coin was made of nickel from 1968. Until 2000, when its composition was changed to nickel-plated steel (92% steel, 5.5% copper, 2.5% nickel). Quarters: In 1968, the twenty five cent coin composition was changed from part silver to 100% nickel for the same reason as the dime. It was made of nickel from 1968 until 2000, when its composition was changed to nickel-plated steel (94% steel, 3.8% copper, 2.2% nickel). Fifty Cents: The fifty-cent coin was made of nickel from 1968 until 2000, when its composition was changed to nickel-plated steel (93.15% steel, 4.75% copper, 2.1% nickel). Loonies: Made of Nickel-Bronze alloy. The one-dollar coin is made of aureate bronze plated on pure nickel. Twonies: The two dollar coin is bi-metallic. This means that it contains two different kinds of metals. The outer, silver-coloured ring is made of nickel and the inner, gold-coloured core is made of aluminum bronze (92% copper, 6% aluminum, 2% nickel). It is Canada's first bi-metallic coin and is one of the lightest of any bi-metallic coins in the world, weighing only 7.3 grams. The Canadian Mint website has a ton of other very cool stuff about our money and I highly recommend you go check it out. You won't be disappointed. http://www.mint.ca/