Diagnostics of Fake and Genuine Unplated Zinc Cents
in Cents, Planchet errors
How to tell a genuinely unplated zinc cent from one that has been corroded, stripped by reverse electrolysis or re-plated — and the surface clues that give each away.
Articles & Info
Articles & Info
Decades of articles by CONECA's attributers and members, sorted by error type, coin series and feature.
Brockage or Not? (Sandwich Coins)
Coins pressed together outside the Mint can pass for brockage errors. Here is how bent rims and telltale damage give these fakes away.
Rockwell Hardness Test Marks On Lincoln Cents
Why the Mint tests planchet hardness, what a genuine test mark looks like on a finished cent, and what is only damage.
Placeholder: Doubled dies on Lincoln cents
in Cents, Doubled dies
Placeholder excerpt for an article about doubled dies on Lincoln cents. Replace with the real article's summary.
Placeholder: Repunched mintmarks on Jefferson nickels
in Nickels, Repunched mintmarks
Placeholder excerpt for an article about repunched mintmarks on Jefferson nickels. Replace with the real article's summary.
Placeholder: Die cracks and cuds on Roosevelt dimes
in Die cracks, cuds & clashes, Dimes
Placeholder excerpt for an article about die cracks and cuds on Roosevelt dimes. Replace with the real article's summary.
Placeholder: Strike-through errors on Washington quarters
in Quarters, Strike-thrus
Placeholder excerpt for an article about strike-through errors on Washington quarters. Replace with the real article's summary.
Placeholder: Transitional errors on Kennedy halves
in Half dollars, Transitional errors
Placeholder excerpt for an article about transitional errors on Kennedy halves. Replace with the real article's summary.
Placeholder: Clipped planchets on Morgan dollars
Placeholder excerpt for an article about clipped planchets on Morgan dollars. Replace with the real article's summary.
Placeholder: Doubled dies on Canadian coins
in Doubled dies, Foreign errors & varieties
Placeholder excerpt for an article about doubled dies on Canadian coins. Replace with the real article's summary.
Placeholder: A new doubled die reverse
in Cents, Doubled dies, Recent Finds
Placeholder excerpt for an article about a new doubled die reverse. Replace with the real article's summary.
Placeholder: Error coins at auction
in In the News
Placeholder excerpt for an article about error coins at auction. Replace with the real article's summary.