Sweden 5 öre 1966, 28,2mm instead of 27mm. This coin has a tapered, conical, edge and a very protruding rim on the anvil die side. All my other partial collars have a rounded flange. What could have caused this tapered shape?
I have a Lincoln Wheat Cent that looks like your coin. I was told that my coin was possibly struck on a type 1 blank as apposed to a type 2 planchet. I do not know if the Swedish Mint uses an upset mill on their blanks or not. The reverse was struck in collar and the obverse is a Broadstrike. I also think that most Partial Collar struck coin are done so at an angle and not perfectly centered. 1 Cent collar slip or luck token | Coin Talk.
Wow! Your coin is very similar to mine. You really had to fight for your case. I am confident in Mike Diamonds answer. Yes, the Swedish Mint uses an upset mill and I think that what we see on our coins is a type one blank that is forced partly into the collar. Though it would be nice to get an explanation to why the edge gets that tapered shape.
I believe the top edge of a die collar is tapered to help facilitate the planchet to fall into place and is above where planchet meets the collar during the striking. But this is speculation on my part. I believe this type of Error coin is quite scarce as it is not readily recognized by most who claim to know about errors. I also note that your coin only has a few bag marks and is in MS condition.
I like your theory, but why doesn't a partial collar on a type two planchet get that shape? Need to find pictures of collars. We don't have that tradition with encasing and bezels in Sweden. So that can be ruled out.
A type 2 planchet is smaller by millimeters and will fall into the collar when centered. When un-centered one side of the coin would have to be resting on the collar die which would result in a Partial Collar Strike. With no collar you will get a broadstruck coin.
I do not recognize the object in the photo you posted. Can you post a link to the site you got it from?
Ok. Yes, I did a Google picture search on cent collar https://sullivannumismatics.com/sites/default/files/pt_coins/images/dsc_0390_1.jpg
