I see this sometimes. More often on pennies than on other coins, maybe just because pennies are what I handle the most of. These came from a bag of old pennies I acquired. They are Lincoln Wheats. The second one is a 43 steel penny. My question is, how many people have to handle a coin by just the date to accomplish this?
I believe the cause not to be handling, but a filled die/dies. Also, steel cents with a partial or missing 4 are surprisingly common. http://www.vamworld.com/Filled+Die
I have a missing 4 steel cent that I found on accident. Its a grease filled die I believe and are more common than one would suspect. Still cool though and keep up the hunt!
Well like I wrote, I see them now and then. Usually I just throw them in the copper coin can because it is hard to sell them on Ebay. Would I list the 191 as a 10, and 11 or a 17, etc.? Is there enough interest in such esoterica to justify the Ebay and Paypal fees that would result if selling for less than $5? Possibly not, so I just throw them into the junk copper coin can. Admitted, the 2 or 3 steel specimens I have just sit in the steel cents can cause I don't know what else to do with them. Maybe pass them at the 7-11?