Lincoln cent color discussion in Baltimore w Merz2
xbob
Posts: 1,979 ✭
I really enjoyed Baltimore yesterday! Did a lot of looking to further my coin education and picked up a 1797 cent (from Jade) and the final Quarter for my mostly circulated Washington collection - a fine 1932 S. I bought it from the same dealer that put me on track with some beginner help at the last show back in July. It sounds corny, but there was a nice karma to finishing my first full set that way.
Lunch with the forum folks was a definite highlight. It was a pleasure to meet all who attended. I thought I might even debunk Tootawl of his namesake (I'm 6'5") but he still had me by about 2 inches. I'm looking forward to the next Baltimore show and hope we can do lunch again. Maybe I'll be able to make dinner next time too.
------- now onto the discussion
Merz2 and I had a discussion during lunch about color variation in early Lincoln cents. I decided to follow-up here so that others could read about it and/or contribute any additional info. The question was - would variations in the copper/zinc mix produce variations in color on the cents in the form of streaks (a "woodgrain" look) on cents. Don talked to a certain company owner (hint: initials - DH) that said any variation like that always indicated cleaning. I had a family dinner last night and asked my father, who has his doctorate in metallurgy and was a metallurgist for the government, what he thought.
The zinc content in early cents is so small that even a variation in the mix should still produce an overall homogeneous color on the coin. However, back then, mixtures were processed in batches (these days it's a continuous run) and variations were more likely to occur. The grain pattern on the coins is probably due to one of two things; 1. An impurity getting into the batch. 2. Improper or irregular cooling of the batch, which produces a crystal-like result in areas referred to as "dendrites". Either of which, when rolled into sheets could produce the striations under the pressure of the roller. He had seen this occur sometimes in his field of Aluminum stress testing, even on the best samples.
Therefore, you were right Don (at least in one metallurgists opinion) that it did not indicate cleaning but a process anomaly.
If any copper and or metals experts read this, please feel free to comment.
BTW, my Dad has a good friend who was at Alcoa and tested and provided clad coinage metals to the mint. If we need to, we'll ask him what he thinks - or any clad metals questions we have.
Hope this info helps.
Lunch with the forum folks was a definite highlight. It was a pleasure to meet all who attended. I thought I might even debunk Tootawl of his namesake (I'm 6'5") but he still had me by about 2 inches. I'm looking forward to the next Baltimore show and hope we can do lunch again. Maybe I'll be able to make dinner next time too.
------- now onto the discussion
Merz2 and I had a discussion during lunch about color variation in early Lincoln cents. I decided to follow-up here so that others could read about it and/or contribute any additional info. The question was - would variations in the copper/zinc mix produce variations in color on the cents in the form of streaks (a "woodgrain" look) on cents. Don talked to a certain company owner (hint: initials - DH) that said any variation like that always indicated cleaning. I had a family dinner last night and asked my father, who has his doctorate in metallurgy and was a metallurgist for the government, what he thought.
The zinc content in early cents is so small that even a variation in the mix should still produce an overall homogeneous color on the coin. However, back then, mixtures were processed in batches (these days it's a continuous run) and variations were more likely to occur. The grain pattern on the coins is probably due to one of two things; 1. An impurity getting into the batch. 2. Improper or irregular cooling of the batch, which produces a crystal-like result in areas referred to as "dendrites". Either of which, when rolled into sheets could produce the striations under the pressure of the roller. He had seen this occur sometimes in his field of Aluminum stress testing, even on the best samples.
Therefore, you were right Don (at least in one metallurgists opinion) that it did not indicate cleaning but a process anomaly.
If any copper and or metals experts read this, please feel free to comment.
BTW, my Dad has a good friend who was at Alcoa and tested and provided clad coinage metals to the mint. If we need to, we'll ask him what he thinks - or any clad metals questions we have.
Hope this info helps.
-Bob
collections: Maryland related coins & exonumia, 7070 Type set, and Video Arcade Tokens.
The Low Budget Y2K Registry Set
collections: Maryland related coins & exonumia, 7070 Type set, and Video Arcade Tokens.
The Low Budget Y2K Registry Set
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Comments
Chris
My Collection of Old Holders
Never a slave to one plastic brand will I ever be.
The Lincoln cent store:
http://www.lincolncent.com
My numismatic art work:
http://www.cdaughtrey.com
USAF veteran, 1986-1996 :: support our troops - the American way.
collections: Maryland related coins & exonumia, 7070 Type set, and Video Arcade Tokens.
The Low Budget Y2K Registry Set
<< <i>It seems strange that a grading expert would say that it ALWAYS indicated cleaning. >>
This is probably the same grading expert that smoetimes sells buffalo chips!!!!...
As far as DH comments, I find myself confused. If he thinks graining is an indicator of cleaning, then how come PCGS slabbed my 09 s vdb, which is all grain.
My Collection of Old Holders
Never a slave to one plastic brand will I ever be.
Anyone who says the striping on the cents, especially the earlier branch mint Lincolns, is caused by cleaning either clearly didn't understand the question or is a blatant novice at the series. They absolutely do NOT indicate cleaning, as I have found a large number of these coins in bags and collections where I know the coins have not been tampered with. It is absurd to blanket ALL planchet striping as cleaning.
I am with your father on this one - that it could have been a number of different parts of the blank making process that caused the problem. I do not believe it was ONLY a metal mixture problem. I have viewed the pattern on enough of these through magnification to tell that it's not a content problem alone. In the same respect, not all of them are caused by the same problem as evidenced by the different "types" of striping. Some of it is very fine sharp lines, and others have muted differences that are easlier to see on a macro scale than through magnification.
The Lincoln cent store:
http://www.lincolncent.com
My numismatic art work:
http://www.cdaughtrey.com
USAF veteran, 1986-1996 :: support our troops - the American way.
collections: Maryland related coins & exonumia, 7070 Type set, and Video Arcade Tokens.
The Low Budget Y2K Registry Set
Chris
My Collection of Old Holders
Never a slave to one plastic brand will I ever be.
If anyone has the knowledge, time, and equipment (and desire) to look one over my example in person, I'll mail one to you. PM your address. Then you can report back what you see.
collections: Maryland related coins & exonumia, 7070 Type set, and Video Arcade Tokens.
The Low Budget Y2K Registry Set
The PR65 is blazing red and the PR68 is a golden tan
Link
Link
Link Fixed
Proof
collections: Maryland related coins & exonumia, 7070 Type set, and Video Arcade Tokens.
The Low Budget Y2K Registry Set
At my end of the table, we were discussing the striations put on the inside of a pint glass as it is emptied of beer and the different patterns induced by the amount of beer drank with each individual swallow and the effect on the thickness of the striations caused by the differences in types of malts and the types of hops used and when the hops were used in the boil as opposed to dry hopping of the beer!!!...
the PR65 is a blazing deep red
the PR68 is a golden light tan
Night and day difference !
Proof
Your reference to zymurgy is waaaay off topic here,unless you wanna talk about Tetnanger or Hallertauer
and the IBU thing,bottom fermenting or top fermenting,pilsners or lambics,weisens.CO2 or natural carbonations.
Never mind !
Proof
All of this talk was while passing around PCGS slabbed coins!..
First and foremost, this effect can be found on ANY date of Lincoln from 1909 through 1982 - it is just far more common on those dated before 1940.
Watersport's Lincoln shows what I believe to be something having to do with the heat generated during the rolling process. It has to have something to do with pressure of rolling (not striking) because of the squeezed and rolled (mushed in one direction) appearance of the grain effect. This is different from the other type of wood graining in that it has sharp lines that are often curved and bent and are close together. I must remind you that this is not an effect of relief - the area around the lines is always smooth and even with the normal surface of the coin.
Coinbuf and Xbob show the other type of woodgraining. This type is what I believe to be a poor alloy mixture in the planchet strips. The bands are often wide and don't have rigid outlines. They also don't show patterns of lines nearly as well as the other type of graining. In addition, the surface of the coin may be somewhat mottled or differ in relief slightly because of the reaction of the improper mix to the pressure of strike.
Both of these are obviously part of the minting process and may show better on circulated or brown coins better than full red coins simply because of the differing reactions metals have to oxidation. They are certainly NOT signatures of cleaning. Neither of these have anything to do with the design on the coin, as cleaning generally does. What I mean by this is that the curves and lines of the woodgraining run right through the design as if it weren't there - because it wasn't when the grain came onto the blank. Lines from cleaning are ALWAYS affected by the design, because the lines came onto the coin after it was struck. Dremmeling, whizzing, wiping, and other forms of abrasive cleaning always bend or change direction slightly with differing relief.
The Lincoln cent store:
http://www.lincolncent.com
My numismatic art work:
http://www.cdaughtrey.com
USAF veteran, 1986-1996 :: support our troops - the American way.
<< <i>The question was - would variations in the copper/zinc mix produce variations in color on the cents in the form of streaks (a "woodgrain" look) on cents. Don talked to a certain company owner (hint: initials - DH) that said any variation like that always indicated cleaning >>
Xbob, I would be shocked if David Hall said or meant that. My guess is that a mis-communication/misunderstanding was involved.
Of course I never mentioned names, just DH. I don't want to get anybody into a feud or anything. Perhaps Don Ho owns a company
Darryl Hannah? David Hasselhoff? could be anyone....
I would agree that DH perhaps he didn't fully understand the question either, especially as in depth and with the examples as we have here. Thanks everyone for the input. Now where's Merz? He's going to enjoy this one!
collections: Maryland related coins & exonumia, 7070 Type set, and Video Arcade Tokens.
The Low Budget Y2K Registry Set
FrederickCoinClub
Registry 1909-1958 Proof Lincolns
I know the IH series better and without a doubt certain dates in full red tend to mellow into specific shades of "red". Early 1880's IH's are known for their deep red/burgandy color. Try finding a gem 1894 that isn't vibrant orange, a tone many other later dates are commonly found in as well. The late 1860's and 70's dates have a more classic mint gold tone. There are still other dates whose reds are usually found with a tannish hue to them. The only reason for this wide variety of "red" that makes sense to me is variations in the quality of the bronze supplied to the Mint during specific minting periods. An old page on a website of mine attempts to illustrate this (link). (Ignore the top 6 coins in the photo since they're copper-nickel, which tones in its own unique way.)
I'm sure early Lincolns have their own common tones just like IH's. I haven't seen enough of them to give specifics but after looking at the Blay Lincolns side-by-side I'm struck by their wide variety of color. For example, do 1914-P's tend to have a deep red tone in high grade compared to, say, 1911's? Lincoln tones seem to become more consistant in the 1930's, I love the wide range of color they bloom into prior to that.
Registry 1909-1958 Proof Lincolns