The Canadian one-dollar coin, often called the loonie, is a gold-colored one-dollar coin introduced in Canada in 1987. It bears images of a common loon, a bird which is common and well known in Canada, on the reverse side of the coin. The image of Queen Elizabeth II is on the obverse side. This is a coin produced in the country by the Royal Canadian Mint (RCM).

This coin is a very popular coin. In the public media, it is discussed and used as the rate at which the Canadian dollar is trading against other currencies. After 2006 the nickname loonie became very widely recognized. The Royal Canadian Mint at that time secured all the copyrights and trademarks to the coin.

This coin's diameter is listed as 26.5 millimeters (1.04 inches) and its weight was originally specified as 108 grains, equivalent to 6.998 grams. In April 2012, the RCM announced design changes to the loonie and toonie (the Canadian two-dollar coin). The changes included several new security features.

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