What causes these surface striations? 1 1

[Mr.Bill347]

1995 zlincoln

nice coin but striated field. What causes this effect?

[DWLange]

The zinc plating does not always adhere smoothly to the brass base on Zincolns. The result can be pimples or stripes that form during the compression of die striking.

[Woods020]

You will often see the term plating blister to reference these. The lines will usually be called linear plating blister versus the non linear pimples. 

[Mr.Bill347]

Thanks Woods and DWLange!

[Mohawk]

Interesting thing I found re-researching German coins.......it looks like the Western Allies almost stuck West Germany with the horrendous and ill-thought out copper-plated zinc alloy of Zincolns that we all love so much in the 1940's, based on this 10 Reichspfennig pattern on Numista:

https://en.numista.com/catalogue/pieces284579.html

[GBrad]

On 1/4/2022 at 4:04 PM, DWLange said:

The zinc plating does not always adhere smoothly to the brass base on Zincolns.

@DWLange. With absolute all due respect, and for clarification in my own mind, did you mean to say "the copper plating does not always adhere smoothly to the zinc base on Zincolns"?  Or is there something I am missing with the minting process of the current Lincoln Cents since the transition in 1982?  Thank you in advance!

[DWLange]

Yes, I wrote that backwards. Never do anything in a hurry.

Gotta run...