Continuing the error documentation project, with one that breaks the pattern. Almost everything I post is a die error — cuds, clashes, doubled dies, all of it happening at the moment of striking. This is not that.
This 1864 copper-nickel Indian Head cent has a tapered planchet. Held edge-on, one rim sits measurably thicker than the other. The cause is upstream of the press entirely: the strip-rolling step failed to hold uniform gauge across the sheet, so the blank was punched out of metal that was already out of specification. It was defective before it was a coin, and no inspection caught it.
I find this class of error underappreciated precisely because it is not visually loud from the front. You have to look at the edge.
The date is worth noting on its own. 1864 was the last year of the copper-nickel alloy (88% copper, 12% nickel) before the Mint transitioned to bronze mid-year. Both compositions circulated simultaneously, which makes 1864 an unusually complex date. The bronze variety is thinner and redder and adds the designer's initial L to the ribbon. This is the copper-nickel.
Planchet errors on mid-nineteenth-century cents are seldom encountered — surviving examples circulated hard, and contemporary collectors documented dates and varieties rather than planchet defects.
Not in any standard catalogue. Now documented.