Metal of little value in America (6)

I believe the answer is:

nickel

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'metal' is the definition.
(nickel is a kind of metal)

I don't understand how the remainder of the clue works.

(Other definitions for nickel that I've seen before include "very little money" , "Five-cent coin (US)" , "Silvery white metal" , "Metal - 5 cents" , "Metallic element; US coin" .)

I've seen this clue in The Globe and Mail.

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