MPD

A misplaced digit, or MPD, is the full or partial (usually partial) remains of a date digit found away from its expected position on a coin.
When a mint worker was adding the date to a working die during production, the worker sometimes tested the consistency and hardness of the die by lightly tapping the date stamp against the die itself. This was typically done on an area of the coin that would ultimately hide the MPD, such as within the denticles. If the die were at the proper consitency and hardness, the full date strike could commence.

Misplaced digits are relatively scarce in the Morgan series, which is unexpected. The first confirmed MPD Morgan was the 1896-P VAM-19, a Top 100 Morgan. Other MPD discoveries have now followed, including the 1884-O VAM-25 and the 1888-P VAM-18, both Hot 50 Morgans, and the 1886-P VAM-21, a Top 100 Morgan with a die gouge now recognized by most as an MPD.
Here is a link to EVERY known MPD VAM... Misplaced Digit
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