Because these early half dollars were struck with an open collar, the outward flowing
Die Deterioration happened fairly quickly compared to modern productions. Eventually the dentils disappeared from the dies leaving a smooth rim.
Below are two photos of the same 1814 O-105a die marriage. The top photo shows much deterioration with half of the dentils missing. The bottom coin shows nearly all of the dentils missing. Therefore we can conclude the top coin was struck likely a few hundred before the second.


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