It looks like possibly a combination of die deterioration and corrosion. The "steel" cents were plated with zinc, and were thus highly susceptible to corrosion. Also, keep in mind that almost since they were originally introduced, people have been re-plating steel coins, and that process also normally mimics the devices and looks a lot like die deterioration. Either way, it's not a doubled die. Keep searching and posting though. Because of the unique die deterioration issues and corrosion, steel cents can be some of the most deceptive in the Lincoln Cent series.
They were not susceptible to corrosion because they were coated with zinc, they were susceptible to corrosion because they were made of steel. Zinc is used on steel to prevent corrosion (rust). Consider galvanized nails. The nails are steel, their coating is zinc. http://en.wikipedia.org/wiki/Galvanization
Sorry Rick, I should have phrased that better and elaborated. The plating was not only very thin, but also did not cover the edges. Because of this, after some circulation the steel would quickly corrode.
Not quite. The zinc coating protects the steel (mostly iron) by ITSELF selectively corroding. The iron should not corrode (rust) until the zinc is consumed.
That's correct, and I think part of what we see on steel cents is corrosion of the zinc, but also the layer was so thin that it easily wore off, and because the edges of the planchets were not coated, this allowed for easy penetration of moisture, etc. In "The Complete Guide to Lincoln Cents", David Lange states that, "A worse combination of metals for coinage could not have been devised by a madman...". It might work fine for nails, but not particularly well for coins. Of course, I'm no chemist, and neither was Lange, but what I do know is that regardless of the mechanism, steel cents get ugly real quick from rust and corrosion. Along with other problems, this was one reason they were so unpopular with the public.
