View Full Version : 1987 D- What caused this...
jlc0321
03-10-2008, 08:17 AM
The picture isn't very good, but where the arrows are the numerals/letters are overstamped into the face creating a shadow effect, if that makes sense.
http://i35.photobucket.com/albums/d177/jlc0321/100_3164.jpg
thanks for looking
Jeff
car10
03-10-2008, 02:15 PM
Can't really tell from the photo.Sorry.
Shingpumps
03-10-2008, 02:27 PM
The generic explanation for that is die fatigue/deteriation. For what really causes it, I would like to know myself.
I've heard it called metal flow lines...not exactly sure what that means either. What ever it is called, all that matters it that it is not worth more than a cent...sorry.
The picture isn't very good, but where the arrows are the numerals/letters are overstamped into the face creating a shadow effect, if that makes sense.
http://i35.photobucket.com/albums/d177/jlc0321/100_3164.jpg
thanks for looking
Jeff
That's easy..It's obviously some photoshoping with either Photoshop CS2 or Paint Brush Pro. You can tell most importantly by the use of the March Green arrows.. I would assume based on the date of the picture and the kodak mint it to be an early March Speciman.
Most likely a computer got ahold of that photo and someone used some green arrows.. Hope that helps..
Shingpumps
03-10-2008, 04:12 PM
You always come through Pat.
You always come through Pat.
ROFL....Just trying to help...:)
A close up would help.
CCC
jlc0321
03-11-2008, 03:23 AM
Thats as close as I can get with the camera I got. I'm looking into getting one of those USB scopes, then I'll be able to post some better pic's.
Jeff
car10
03-11-2008, 03:59 AM
Thats as close as I can get with the camera I got. I'm looking into getting one of those USB scopes, then I'll be able to post some better pic's.
Jeff
You might try putting your loupe up to the camera lens.
jlc0321
03-11-2008, 05:59 PM
Believe it or not that was with a 2X loop against the lense, I took several pictures but that ended up being the clearest one. I'm going to get one those handheld scopes, I can use it for my rock-hounding also.
Jeff
trails
03-12-2008, 07:15 AM
Metal flow lines are fairly simple to explain.
When the dies strike the coin, you have what is called "cold metal flow'. This is the ability of the metal to flow from the center of the planchet to the outer edge, filling in the recessed designed elements as it flows. The reason behind the "cold" part is that this is done without the application of heat to soften the metal.
This cold metal flow not only affects the planchet being struck, but also the die as well. When each coin is struck, a small amount of atoms from the die's surface are peeled away. The design elements tend to impede this metal flow and sets up areas of low pressure and higher pressure along the die surface. The lower pressure points will have more erosion than the other points of the die surface thus peeling away more of the atomic structure on the die in those areas.
One analogy is to think of ripples in the sand caused by water flowing over them. Or the washboard affect on a very well traveled dirt road. In both instances, the rippling effect is cause by movement over the given surface and the erosion caused by that movement. Great examples of this are the "poor man's 1955 double die", which also happened in 1953 on the Lincoln cent or any of the ghost images that are created by die deterioration.
Now the tricky part. Metal flow is not at a constant speed throughout the strike. It gains speed as it radiates from the center. This is basic physics and it application to momentum and amount of mass being moved. The reason for this one point is that the faster the metal flow, the more of the die's atomic structure is eroded. This is why die deterioration begins to form noticeable near the outer edge of the die.
One other point to bring up concerning metal flow is "the path of least resistance". This is the tendency of the outward bound metal flow to take the path that offers the least resistance to its flow. Once a grove, no matter how small it is, is established, it will offer a path of lesser resistance. That means more metal flow, more erosion, lesser resistance in that grove in an escalating process. That groove becomes more eroded and deeper after each strike than the surrounding areas. Thus the formation of radial lines along the outer edge of coin struck with a late die state die.
There are other affects caused by die deterioration that are related to metal flow and once you have the understanding of just what goes on during the strike, these affects are easily figured out.
BJ Neff
Shingpumps
03-12-2008, 08:34 AM
Freekin awsome. I finally understand. Thanks for telling me how that happens. Your the first person who could tell me what deteriation is.
Great explanation Trails! Now I get it. Are Steel Cents more likely to show "metal flow lines? than copper?
trails
03-24-2008, 03:07 PM
Sorry that I did not get back to this post Brad, but I'll try and answer it now.
The steel planchet of the 1943 Lincoln cent tended to wear the die even faster than the copper planchet that was the norm for the cent. Since the metal flowing over the die was now a harder metal, it would stand to reason that the die would erode faster with more atoms being worn away with each strike from the flow of steel on steel (even though they were of different hardness).
Oddly enough, we may see this happen again for there is talkof bringing back the steel cent, chemicallt treated to appear as copper. Canada already uses a steel cent that I believe is copper coated, so the technology is in place.
BJ Neff