Nickel – the element – is a recyclable, non-ferrous metal mostly found in alloys or present with other metals. Plating would be a good example. Meanwhile, a nickel – the U.S. five-cent coin – is actually 75% copper and 25% nickel. The five-cent coin in current circulation is called the Jefferson nickel because it bears the profile of President Thomas Jefferson. Before the United States of America ever was, the North American colonists used a five-cent piece called a “half disme,” or half dime. That coin was minted from silver.

Source: Cohen