1970 D Struck on Improperly Annealed Planchet

[Rowdyricster]

Browsing through one of the books I recently ordered (Official Price Guide: Minting Varieties and Errors, Fifth Edition by Alan Herbert), I found a picture of the reverse of a coin that reminded me of one I had set aside (what can I say, I'm just curious). Anyway, Herbert describes that coin as Struck on an Improperly Annealed Planchet. He says, "A coin struck on a hard planchet will have poor metal flow into the design and may easily be confused with a weak strike" (p. 179). My coin looks strikingly (pun intended) similar to the one pictured in the book. Since this edition of the book was published in 1991 (and there were at least two editions after that one), I don't know if that diagnosis is still the general thought. Thoughts?

Obv.jpgRev.jpg

[mustbebob]

It is difficult to say this coin suffers from an improperly annealed Planchet. I would tend to think a grease filled die is the more logical answer. Remember that the improper annealing affects the entire planchet. Your coin has most areas (especially the reverse) perfectly struck. I don't see where it was difficult for metal to flow in these areas.

[Rowdyricster]

It is difficult to say this coin suffers from an improperly annealed Planchet. I would tend to think a grease filled die is the more logical answer. Remember that the improper annealing affects the entire planchet. Your coin has most areas (especially the reverse) perfectly struck. I don't see where it was difficult for metal to flow in these areas.

Thanks, Bob. I am sure you are correct. In doing some further research this morning, I found this thread from 2013 in which JC Stevens asks the same question, but regarding a different coin. I'm sure he was probably reading from the 7th Edition, so I dont know if the photo is the same as Herbert listed in the 5th Edition. Mike Diamond commented in post #4 that "It's debatable whether the cent Herbert used to illustrate this category actually represents a non-annealed or inadequately annealed planchet". I realize knowledge in this field has expanded exponentially even since the 90's. I was just struck by the similarity of my coin and the one Herbert used in the book.

Added: In the book he only shows the reverse. Your point of it affecting the whole planchet is well taken. Thanks again!

[jfines69]

Very interesting... I'm with Bob on the greaser... The only info on improper annealing I found on Error Ref covers Cu-Ni clad and copper-nickle planchets... Also some info on weak strikes... Other than that I'm lost

[GrumpyEd]

Probably grease caused the reverse to be that way.

Along with, that area is also prone to not get fully struck up because it is the jacket on the obv so metal is trying to fill the jacket like the many modern ones missing the O of OF and weak on the EPU and building top. Sort of like why we see weakness opposing a cud since metal is filling a cud, metal filling the jacket causes a similar but lesser effect on the opposite side.

On the obv the thin motto and RTY is on a lot of 70-71 cents, to me some look like they should have hubbed them again but maybe it was skinny upstream of the dies because it's like that on many dies. Even the 70-S SD has it to some extent and they are multiple dies.

Bottom line, the planchet probably was normal.

[Rowdyricster]

Thank you Jim and Ed! I had always assumed those type coins were the result of grease filled die, and never really gave it another thought...until I saw the picture in the book I cited, which caused me pause. I cant say I've seen one exactly like it before (which is why I set it aside) but I've seen lots where EPU and STATES OF is affected. I am quite satisfied that you are correct! Everything I've read about struck through grease fits perfectly with what you're saying. In a post I linked to above (#3) Mike Diamond questioned whether the picture Herbert used was, in fact, a good example of improper annealing. (If you guys have a copy of the book, it's on p. 179). Ed, I especially appreciate your detailed explanation. You make things easy to understand. Thanks!

[jfines69]

You are welcome... Wish I could have done more for you!!!