Did some more online research. Closest I can guess at would be orange peel effect? Or are these zinc bubbles?
I think we should all give a round of applause here for a new member who DOES HIS RESEARCH!! Definitely "Orange Peel" effect you've got.
I have to admit I cheated. I looked it up before I even joined the board. Just wanted to get confirmation that I wasn't barking up the wrong coin tree, as it were. Thank you William! Anybody know what causes it?
The coin has plating blisters, it is a copper coated zinc. Orange peel is completely different and not something you find on Zincolns. You find the plating issues most commonly in 1982-1983 cents since this was the first two years of production.
That's the main reason I collect solids in lieu of 'sandwich' cents...The 'coppers & brasses' have enough problems of their own. (I do fret over the 1943 issues) J.T.
So according to http://www.error-ref.com/blisteredplating/ it says: "Plating blisters are hollow. They look similar to, but should not be confused with, solid blisters pushed up by subsurface corrosion. Solid blisters are pushed up by gas under the expanding metal." So these are blisters formed at plating time... er from gas captured during plating I suppose?
When the planchets are being blanked out of the sheets of Zinc, manufacturing materials are used to keep the tooling lubed extending the life of the die between sharpening. Normally, water soluble lubricants/oils are used as they are easiest to removed during the cleaning/rinsing process. If this oil isn't sufficiently removed, it can become problematic when the planchets are sent to the plater. During the plating operation, the plating might not bond with the zinc substrate in areas creating voids. Where the bond is weak, it can lift and separate from the substrate. If there is a split or a hole in that area, then the environment can take over, creating the eventual conditions to support the creation of hydrozincite. We tend to call that 'zinc rot' around here. The substrate zinc is eventually consumed by the environmental conditions. Air and humidity are the key factors to creating the hydrozincite. Zincolns lost in the cupholder of a car, where cold drinks sweat and temperatures can get high, accelerate the road to destruction. You can see on your specimen that the issue is present on the obverse and reverse. Suggests a dirty bath before plating to me affecting both sides.
Orange peel on Lincolns is very uncommon. The mint did some experimenting with sandblasting production dies - similar to what they did with the early proof Lincolns. Nobody knows the exact nature of their experiments but the result can clearly be seen in some non-proof dies. Notice the fields on this coin, it's one of a few that I own that have REAL orange peel fields, it's a 1910.
Here's one of my 1909's (toned in the same silver/gray as the 1910 above), you can see the same orange peel in the fields.
