The only way to be 100% sure it's a mint problem is if you got it out of an uncirculated roll or bag, other wise, like my dime here, it's road kill, flat, or if it's a real error, sorry, can't help. But it looks very worn out to begin with, that must have been an attempt to flatten a penny on a railroad, in '57, it's possible!
any way to get a reverse picture and also a pic taken with a camera at a different angle? it's kinda hard to see the flattened area
It could be a laminated error with a layer that fell off. Can you posts some more picks like xeno108 has asked?
Unless the apparent "out of round" shape is an optical illusion from the camera angle, it's enough to convince me we're looking at post-strike damage from an application of force.
Now those pics make a difference. The "In God" wouldn't show in the missing metal area if the damage occurred post-strike. Since it does faintly show, the planchet must have been defective when struck. I don't know enough about error collecting to even guess whether that kind of dmage is considered a collectible error or not.
Like mine, I've seen many of these. Don't think it's that valuable. Now, If you got it from an uncirculated bag, there's a different story. (Yay! 101 Posts for me! My favorite palindrome!)
