What causes “Orange Peel” on proof coinage?

[Newmismatist]

This thread is related to a previous thread posted by Carl Wohlforth across the street showing a Jefferson nickel with quite “rough” surfaces. Carl asked the question: “What causes this "orange peel" look? The response was pretty universal that the look of the Nickel that Carl posted was from die wear or die deterioration.

 

Link to Wohlforth thread

 

Shylock posted a picture of an Indian Head cent that had “Orange Peel” surfaces. This resulted in a discussion as to what caused this “orange peel” look and also, exactly what were we talking about. Although the look of die wear in the fields of a coin does have somewhat of a roughness like the peel of an orange, the reference to an “Orange Peel” surface has it’s origin from the car painting industry. When the auto industry switched from enamel paint to lacquer (I think in the 30s or 40s) a new phenomenon appeared - an “orange peel” look that resulted when the coats of painted were applied a little too heavy. This is the “orange peel” look that Shylock and I were referring to. Here’s a paraphrased discussion of orange peel as it relates to auto painting:

 

"orange peel” is old nemesis to painted finishes. Any way you look at it, orange peel is bad news. When a car rolls off the assembly line with this wavy, light-and-dark pattern hiding somewhere in the paint - that’s bad. While paint makers have succeeded in developing very high gloss liquid coatings, there are still underlying problems in controlling waviness (orange peel) in the final appearance of finishes.

 

It’s exactly this “waviness” that Shylock was trying to depict in the proof IHC that he posted. It is extremely difficult to photograph this effect, but once you’ve seen it on a proof gold coin or an IHC, you’ll understand why it's referred to as an “orange peel” look.

 

Now here’s a couple of observations:

 

I have only seen this on 19th and early 20th century proof coins - specifically proof IHCs and proof gold. I’ve never seen it on modern US Mint proof coinage (1936 to date). It’s a somewhat shimmery look - like sunlight reflecting off of water. I have sometimes seen it is described as a "Watery" look in auction catalogues.

 

Here’s Rick Snow’s (Eagle Eye Rare Coins - he specializes in Indian Head Cents) description as to how this occurs:

 

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.”

 

I would add that the dies don't have to be re-polished for this look to disappear - after the first few coins are struck, the metal to metal contact from the striking process has its own "polishing" effect and the waviness is minimized to the point where it is no longer visible on the struck proofs. (The same is true regarding the Cameo look of the first struck coins: after successive strikings, this cameo looks disappears, I believe due to the die wear that has initially "polished" away the "roughness" of the recessed devices of the coin die and perhaps also the filling of the recessed portions of the die with dirt, dust, oil, etc. that would tend to minimize the "cameo frost" on the struck coin.)

 

Some of of the PCGS forum members who are familiar with dies, metal hardening and the minting process have questioned this explanation, but I tend to agree with Snow’s description because my experience is that you only see this look on early strike 19th century proofs (and the 1st few years of the 20th Century), the same coins most likely to exhibit a cameo look.

 

Can anyone add to our understanding of what causes this "orange peel" effect?

 

Is Snow’s explanation of what causes it correct? or is there a more detailed or better explanation?

 

Has anyone seen this look on proof silver coinage or Nickel coinage?

 

Why doesn't it appear on modern proof coins? (Or does it?)

 

 

 

[Hoot]

Newmismatist - I can't add to the information on proof coins, but I do have an observation on the thread across the street. It's clear that the term "orange peel" means different things to different collectors. I found the arguments a bit humorous because each "camp" (if you will)was trying to argue as if there is a singular meaning. It seems obvious that there is one meaning for proof coinage and one for circulation strikes (and perhaps others). I was only familiar with the latter, as fatigued dies of circulation strikes of Jefferson nickels often impart an orange peel effect. It's essentially a late die state deterioration where flow lines are broadened and irregular "pockets" of metal are formed in the flow lines causing the dimpled effect.

 

What I found disturbing about Snow's description is that several die workers piped up on the other thread and indicated that the bulk of die polishing occurs after the dies are hardened. I had always thought this from reading about the minting process, both 19th and 20th century. My reading is limited, however, to ANA material and a few other numismatic references and so it's not the most in-depth. Still, I find Snow's description odd and counterintuitive.

 

I'll let others fill in the blanks, but I have a suspicion that as minting technologies changed over time, so did the impartation of the quality of the orange peel effect on proof coinage.

 

Hoot

[jtwax-migration]

This is a great topic and one that I will through in my 2 cents on.

 

I am a Jefferson nickel collector only and see the "orange peel" effect on many business strike Jeffersons, particularly from the 50's and 60's (as well from the 80s). I have however never seen the effect on any proof issues from the Jefferson series. I have also seen this effect on some scattered Lincoln business strikes.

 

To my understanding the "orange peel" effect is caused by overheating during the annealing process. I also tend to believe that die deterioration plays a factor in the scenario. Because I only collect variety coins I have never seen an EDS variety with orange peel. So really, I think it's a combination of both.

 

A couple things I have noticed (as far as the Jefferson series is concerned) is that I believe orange peel virtually does not exist on any silver issues, which tells us that the planchet metal content has a pertinant roll in this effect. As well, it is a completely random matter; sometimes appearent on the reverse and obverse in combination and sometimes either or, perhaps mostly on the reverse and believe that the reverse is most suseptable on either side of MONTICELLO, in the narrow field between that and the rim. I have also never seen it anywhere on any of the design elements and only in the fields.

 

[Leothelion]

I've never seen it on proofs either, perhaps, I've missed it. But it will appear on the devices for business strikes, especially on the Monticello. It depends on how worn the die gets. The 53-S, 54-S, 56-D and 61-D are likely candidates for extreme orange peel. I particularly don't like it on my coins and sadly the TGC's and most sellers rarely look for it or mention this about a coin in their auction descriptions. It really goes to show how much most folks know about nickels.

 

Leo