1942/41 Mercury Dime, NGC XF40
In 1941, toward the end of the year, 1941 10c dies were still being made as well as the dies for the coming year, 1942. Two of these dies became involved in an accident that created one of the few rarities in the silver “Mercury” dime series.
Coin dies are made in stages. To make a die able to strike coins, the design must be stamped into it twice by a master die or Hub. Between each impression, the unfinished die must be heated in a process called annealing. A 1941 die and a 1942 die had both received their first stamping; now both dies were being annealed. When the dies were returned to receive their second stamping, the dies were accidentally switched. When they were stamped, both dies now had evidence of both the 1941 and 1942 date.
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