What causes this "orange peel" look?

CarlWohlforth

I photographed this nickel and the surface looks rough like an orange, especially the reverse. Can someone help me learn how this came to be?

airplanenut

If you look closely at the fields, you'll see they aren't perfectly smooth (proofs are much smoother)... the lighting you use accents the roughness by casting shadows... and that's the look you describe.

Jeremy

Fairlaneman

Late die state I believe ,Carl

Ken

1jester

I agree with Fairlaneman. And APNut.

baccaruda

Yep, die deterioration. I don't find it unattractive though.

jonesy

I thought that was metal flow!!

CarlWohlforth

Thanks for the comments so far!

Metal flow (striations) looks more like lines radiating out from the center. This coin is not like your average Jeff. I can imagine a die getting a little pitted after a long life and producing a nickel like this. It is interesting.

baccaruda

Carl -

I have one that looks very similar, maybe even "worse" than yours. I think it's one of my best looking Jeffs. Strangely enough, the severely deteriorated die that caused that doesn't seem to have affected the steps - on yours or mine.

paigowjohnny

Poor annealing of the planchets

Rittenhouse

It's called die erosion. The friction of striking gradually erodes the die. Most often seen in the fields due to the large flat surface. It can be lapped out, but the Mint usually doesn't bother these days given the relatively low cost of dies and number of strikes they can get b4 they get really bad.

coppercoins

It is die deterioration from striking the harder nickel planchets. 'orange peel' is a term usually reserved for the zinc cents with gas bubbles trapped underneath the copper plating. Different appearance, different cause.

EagleEye

Orange peel is used to describe early die state proofs (pre-1936) where the field looks crystalized instead of perfectly flat. You see it mostly on gold proofs, since they are mostly all early die state pieces. I've never heard the term applied to zinc cents or late die state coins. The late die state coin shown is caused (as has been said) by die wear. The metal flow is the cause of the die wear.

Blade

Cool! I've got a couple Jeffs like that. Can't remember the dates. Pulled them out of circulation in the early 80's. And "orange peel" is exactly what the local dealer called it back then. So perhaps the term has been used for different purposes over the years, but orange peel is (or had been) a commonly used term for this type of surface.

Unfortunately I never learned the cause. I'll buy late die state, though.

keets

hey Carl

it seems we have agreement on cause and now the battle will rage over terminology!!! i've always called what you're seeing "orange peel" and considered that to be a generic term for the appearance of the surface and not necessarily a term for how it was caused or what alloy it's seen on, and certainly there isn't a time frame restriction on the term. perhaps those mentioned can lay claim to the origin of the term and responsibility for its widely accepted use, but past that??? c'mon guys, it's a numismatic term.

al h.

dorkkarl

don't think the proper term for carlwohforth's nickel is "orange peel", which is a term for early proofs / p/l strikes. the nickel shown just exhibits advanced die wear.

K S

IrishMike

I believe dork and Rick have explained what I have always heard too. Proof IHC's with the orange peel look are highly valued and many times they look orange, same with gold.

clackamas

Everyone has been calling it die wear but look at the stike on that coin. Does that look like a worn die? Its a metal flow issue IMO.

shylock

I've always heard orange peel used in reference to early proofs also, the result of early state dies that had been polished. On early copper it's a very desirable look, here's one that's also orange.

Cam40

Sometimes these deteriorating dies are pulled and polished back to health so to speak. Then instead of the orange peel look the fields on the coin will have these tiny raised lines that look like cob webs sometimes.
At first I thought these raised lines were hairline scratches, as in post-strike alterations from a harsh cleaning.
These tiny lines can be deceving to the untrained eye. I think they are technically called die-polish lines.

I notice die state on a coin almost right off the bat when searching stuff now. Is it early die state, medium die state, late die state, die polish lines, die cracks, machine doubling etc.

oreville

I have also seen orange peel used to describe the color of mint state copper coins (mostly IHC and earlier lincolns) that exhibit that lovely and heavy mint frost and color.

CarlWohlforth

Thanks for the interesting and informative responses. I had heard the term "orange peel" but didn't know exactly what is was used for. When looking at this Jefferson nickel that term popped into my mind.

Thanks for the photo Shylock! It really helps me understand what an early die state proof IHC looks like. I would love to examine that one in person.

I don't care for the look so much. It reminds me of a Philippine peso we have that was recovered from Manila Bay. It was eroded by salt water in a cresent pattern because it was partially covered by another coin.

This coin was graded MS 64 Full Step by PCGS. Even though the steps are not totally full (they look like 6-5-5-5 steps to me) the coin is well struck.

rkfish

We also see what is called "orange-peel" in the Peace Dollar series
especially on the 22-d and 24p......and rarely on the 23p and 25p.

IMO it's also surface roughness due to excessive die wear......

Newmismatist

Here's a more descriptive explanation of "orange peel" as it relates to proof coinage (Courtsey of Rick Snow & from one of my articles on Proof IHCs):

"After the dies are hubbed and the date is applied, the die is given multiple polishes with progressively finer and finer polish. The last polish given to the dies prior to being hardened gives the field a surface quite like a mirror. This is the deepest mirror attainable on the dies. When the die is hardened, the metal shrinks slightly creating a wavy effect on the polished surfaces. It looks somewhat like the surface of an orange. When you see orange peel on a proof issue you can be sure that it is one of the first examples struck from those dies. Later polishing to the already hardened dies will produce a flatter and shallower mirror."

On the Jefferson Nickel shown in this thread, what you are seeing in the fields is definately NOT orange peel surfaces, it is die wear or die deterioration. The fields on a coin are the lowest (deepest) portion of the coin, hence the highest portion or "face" of the die - thus for every coin struck, the highest part of the die strikes 1st and "moves" the most metal, thus this part of the die wears out first and more dramatically than the recessed parts of the die. (The devices are recesssed on the die, hence raised on the coin).

To understand what happens in the coin manufacturing process, think of a hammer with the center partially hollowed out. When you continuously strike an anvil (the lower fixed die), the face (lowest part) of the hammer will get marked & dented from repeated blows, while the center will remain mostly unmarked - & the same is true of the anvil die. Detail that is "lost" in the recessed parts of the die (Full bell lines, split bands, etc.) is also compromised by die wear BUT also results when those parts of the die become filled with microscopic bits of metal, grease, dirt etc, so the loss of detail on the highest parts of the coin will tend to be from filling of the dies with dirt, machine shop greases, oils, dust, etc. all of which once in the recesses of the die prevent the full detail from being struck. So a scenerio where a worn die was cleaned by degreasing with a cleaning solvent, pressurized steam or even soap & water & then blown dry with compressed air - could likely strike a coin with fields like the ones shown, but sharp detail in the highest parts of the devices. Making coins is a high speed manufacturing process with all the attendent dirt, grime dust, etc., present in a factory environment.

WorldTypeSet

I photographed this nickel and the surface looks rough like an orange, especially the reverse.

This effect is often seen on Canadian 5c pieces from 1922 to 1936, and is called an "orange peel" effect - by us Canadians. It is caused by die erosion from striking the hard nickel planchets.

RNCHSN

die erosion.

keets

i think we can all agree that what we're seeing is from worn dies. why is there so much confusion over the fact that many collectors refer to it as orange peel?? it's simply a descriptive term, and in that regard a very good one.

al h.

hamiltonjh

I kinda like the look of the pics.

greghansen

I can see the need to properly narraw and define what 'orange peel' surfaces are. It is only a descriptive term as Al H. observes, however, it describes a coins surface produced by a very specific die preparation as described in earlier posts. The Nickel, however, shows surfaces that look similar but are the product of a much different result. The Nickels surfaces may be 'orange peel like', but they aren't 'orange peel'.

An appropriate analogy would be Morgan Dollars. We don't call a 'proof like' business strike a 'proof' coin simply because its surfaces mimick that of a proof coin. The term proof is properly limited to coins produced from a specific die preparation process. Business strike coins which have similar appearing surfaces are properly called 'proof like'.

Conder101

The term "orange peel" dates back at least thirty years and as far as I know it has always in my experience been used to refer to the texturing of the surface of the coin caused by worn dies that are experiencing heavy metal flow from the repeated pounding and expantion of the coinage metal across them. This thread is the first time I have heard it used with respect to the surfaces of a proof. And I can't buy the explaination of orange peel on the proof surfaces being from the shrinking of the surfaces of the die during hardening. If the die face was polished before the heat treating used in the hardening process the oxides that formed on the die face which would have to be cleaned off after hardening would destroy the mirror finish. For that reason the dies are polished AFTER hardening. I would think that the orange peel seen on the early proofs are also caused by die wear but since the mirror surfaces of the die are so delicate the pebbly appearance appears fairly soon after the dies are put into use. (On the glassy smooth surfaces the wear is visible much more easily and therefor is noticeable very quickly.)

shylock

As per "orange peel" in reference to proofs: I believe the dies were polished while they were still soft and hadn't fully hardened. Not before they were heated but while still cooling off, so some additional shrinkage took place.

keets

well now, since the scientists and metallurgists always seem to come into the threads where "collectors" are talking about dipping coins and the effect on the surfaces, it seems we need the machinists/tool-and-die-makers to come into this thread instead of just having idle speculation. with the type of work i've done in the past, we would sometimes grind the surfaces before heat-treating and re-grind after, but we always grind after rough machining and the subsequent heat-treating for surface hardness to acquire the proper size/surface finish. then if there was a surface finish that wasn't able to be accomplished in that fashion, we would either lap the surface if it was cylindrical or send it to another vendor if it was flat. in all circumstances, there is an effort to keep the part from heating while its being worked on to prevent shrinkage when it cools and the resulting distortion. i would assume the mint prepared dies are worked on in a similar fashion. they're probably polished, checked for micro-finish and then used. you can't have a 2 micro finish or a 4 micro finish and have the surface appearance that y'all are describing. it simply comes to that as a result of wear.

al h.

Rittenhouse

<< <i>well now, since the scientists and metallurgists always seem to come into the threads where "collectors" are talking about dipping coins and the effect on the surfaces, it seems we need the machinists/tool-and-die-makers to come into this thread instead of just having idle speculation. >>



Already happened Keets, you just didn't know it. I spent quite a few years as a process and quality engineer in the metals industry, including die forming. Your experience and Conder101 comments are also well founded. Like Keets, the companies I worked for always polished AFTER heat treat due to oxidation & shrinkage effects.

Snow's description of "orange peel" on IHCs is HIGHLY suspect. He never supported his claim with one shread of evidence from a Mint source. I spoke with a few folks from the Mint some years ago, including Howard Toll who was the Plant Metallurigist at the Philly Mint. All responded in exactly the same manner. They weren't sure what caused the so-called orange peel effect as they'd never seen it. I never made relective finish dies so wasn't sure either. They, as I , suspected a surface effect due to a faulty polishing process. Whatever, Snow's argument doesn't hold water.

Oh, forgot to add that the Jeff that started this discussion DOES NOT show orange peel. As I and others commented, it's classic die erosion caused by the friction of striking. Easy to tell erosion as it spreads radially out from the center following metal flow. Always heaviest in the fields as they receive the most abrasion. Dies that strike harder metals (nickel, CN) will erode faster than dies used on softer metals. It is not caused by impact. Actually there's little "impact" during the striking process. In the US, all presses since 1836 have used a progressive squeeze rather than the classic impact method of screw presses. However, the pressure can cause dies to crack, buckle, and chip-out.

If you want to learn more about this, go to the library and get a book called "The Metals Handbook"; check out the sections on heat treatment of ferrous metals and the one on failure analysis and prevention. The "US Steel Handbook" is also a good source.

Gilbert

I was with Coppercoins up to this point,

It is die deterioration from striking the harder nickel planchets.,

as I am sure I've read this, and also heard this term used in describing Morgan dollars struck with later state and deteriorating dies., but, WoW, don't really know who the authority is, or if these statements really conflict with that authority, but it makes sense to me.

shylock

Here's Snow's description which I just found online.

"Orange Peel fields. A real joy to behold is a gem early die state proof. These will have deep mirrors, frosted devices, and orange peel fields. When the dies are first made the steel is soft so that the design and date can easily be impressed into it. While the dies are in this soft state they are given a very fine polishing. After the die is hardened, the steel contracts slightly creating a wavy look on the polished fields. It looks like orange peels! After a small striking period the die may be reground and the orange peel will be wiped away. These later proofs will not have the deep mirror cameo appearance of the earlier die state pieces."

Rittenhouse

Shylock, we already know what Snow sez, Newmismatist quoted it several messages above. As I said, Snow offers no proof for his conjecture. Furthermore, what Snow sez is in conflict with memebers who've done this work AND the comments from folks at the US Mint. If Snow wants me to buy his argument all he needs to do is come up with a competent authority (i.e US Mint record or metallurgist from a minting facility) to support his currently unsubstantiated claim.

Nic

This term, to me, is used in reference to the look of a few unmolested early strike proof gold and to lesser degree copper coins. When you have seen the look you will never forget. Not die wear. Rarely seen on silver. Perhaps it is in part due to early proof striking of SOFT metal? K

shylock

Rittenhouse - I felt Snow's explanation was stated more concisely in the excerpt I posted, which may help those reading this who aren't as well versed as yourself. How would you account for the wavey surfaces in the fields on the IH proof I posted?

Rittenhouse

Shylock,

Since I haven't studied this area other than to make some brief inquiries on Snow's comment, I've nothing to offer than what I've already posted. This would be a good subject for serious study. MIGHT be something in the Mint records.

Newmismatist

A couple of observations: THe proof Orange Peel that has been referred to by Shylock, Myself and several others appears for the most part on 19th century coinage & the 1st few years of the 20th century - In 1909 the mint change from brilliant proof finish to matte proof finish thru about 1916 (though there may be a few proof strikings in 1917). Proof coinage all but ceased until 1936, and when it resumed, the finish was again brilliant. I have not noticed an Orange Peel surfaces on modern (1936 to date) coins - (that doesn't mean it doesn't exist). So IMHO, discussions with current mint employees as to current production methods will not answer this question. I believe that proof coinage was produced "differently" pre-1909, than post 1936. First of all more coins were struck, so the methods used may well have been different than in the 19th century. That observation aside, consider this:

1. Orange peel surfaces appear most often on 19th century proof gold - coins which for the most part had very limited proof production runs.
2. On proof IHCs very few coins exhibit orange peel surfaces AND it is more evident on Cameo proof IHCs than non-cameo IHCs.
3. Cameo Proof IHCs are most probably the 1st strikes from the dies - the recessed portions have not yet "smoothed out" from metal flow (or other contaminents that might adhere to the recessed portions of the dies that could not be wiped clean).

I would conclude from the above that the proofs struck first from "fresh" dies will most likely exhibit both orange peel and (or) cameo, (but one does not guarantee the other). I would also conclude that later struck proofs will be far less likely to have either orange peel or cameo effect, so for whatever reason orange peel results from "new" dies. Why, I don't know, but whatever was done by the mint to the dies in the 19th century, is not necessarily how they make and use them today (and since 1936, when proof production resumed).

When I put together my registry set of proof IHCs, a significant number of my bronze IHCs were cameo (and so designated) and similarly, many had orange peel surfaces. When I was collecting proof gold, I observed the same orange peel and cameo effects. I believe that both result from 1st strike coins from "fresh" dies.

I think this would be a great area for further research.

Conder101

<< <i>As per "orange peel" in reference to proofs: I believe the dies were polished while they were still soft and hadn't fully hardened. Not before they were heated but while still cooling off, so some additional shrinkage took place. >>


Hardening of the dies involved heating them up to a certain point (don't know the specific temperaature and it will very depending on the steel used dull red, cherry red yellow red etc) and then cooling the steel down again VERY rapidly, as in a matter of seconds, by quenching with or in water, oil, mercury etc. You are not going to be doing any polishing during that process.

IrishMike

With all due respect to the machinists, die makers etc. other than 3 summers working in a screw machine shop I have no expertise on this subject and readily admit to it. Newmismatist has pointed out very well his experience based upon ownership of the coins. If you look at the coins that present this look you can deduce that something was going on with these dies and we may never be able to prove exactly what it was. Where are Scully and Muldur when you need them? Anyway they are prized possessions for IHC collectors.