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Roosevelt Dime Obverse Missing Clad Layer

Modern coins consist of a copper core sandwiched between a copper-nickel clad layer and his includes dimes, half dollars, quarters and most Eisenhower Dollars that were minted from 1965 until the present. Further note: Some Kennedy Halves and Ike Dollars have a silver clad layer, but if any are missing the clad layer it reveals their copper core.
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Lincoln Cent Missing Copper Plating

In 1982 the U.S. Mint begin using zinv planchets plated in copper for U.S. Lincoln Cents, some 1982 issues are copper, and there's been a report of one 1983 copper planchet cent discovered.
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Missing Clad Layer Mint Error
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