Both faces show cracked copper plating overlying a low ridge ring.
Chemical damage. Alan Herbert called these "sewer coins", presumably because raw sewage can create this effect over time.
The mate for this coin would naturally be an off-center half dollar with an unexpanded, low-pressure brockage of the obverse design on its reverse...
This half dollar is an in-collar double strike with a low-pressure indent on the second strike. Minimum die clearance during the second strike...
The fact that copper is peeking through on the high-relief, slightly worn portions of the obverse design indicates that the silvery metal was...
I see two strikes delivered in succession. Not a saddle strike. The slide zone on the larger strike is too wide, the wrong part of the design is...
Most British coins are struck with the reverse die functioning as the hammer die. If that was the case here, then this brockage appears on the...
Thanks for posting excellent photos. This does not look like glue. It does look like a genuine error from here, but one that I have no...
The serrated rim on the right side is post-strike damage. A fin would not show a serrated edge. Even fins on reeded coins don't show serrations.
It's not a dryer coin, but it was altered outside the Mint.
It's a reverse (anvil) die cap. No more than two strikes were necessary to generate it.
Struck through grease. In Kennedy halves, grease deposits are often thicker opposite the eagle's breast. Hence the depression on the side of...
Since the fracture line is stepped and extends from one point on the rim to another point on the rim, it would be classified as a retained cud of...
Belief shouldn't enter into it. The weak but complete 5c image and the soft, blended overlap between 5c details and the 1c design clearly...
This is a genuine cent struck by a pair of counterfeit 5c dies.
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