Saw some doubling on the "United States of America" on the reverse of this 1991 penny. It doesn't look like machine doubling to me but I still struggle to identify the difference. Opinions?
DDD is Die Deterioration Doubling. http://doubleddie.com/144843.html This is a worn die issue same as the ridge ring on the reverse of your coin. http://www.error-ref.com/?s=Ridge+ring
I read up on it, but it doesn't appear (based on my limited understanding) to fit the profile for inside or outside abraided doubling. Wish I had a coin microscope
Oh don't misunderstand, I'm not questioning the validity of your statement at all. I'm lamenting my inability to see the difference lol