Re: How are US pennies made?



Jeff Wisnia wrote:
Gary A. Gorgen wrote:



Jeff Wisnia wrote:


How are the current copper/zinc pennies manuafactured?

My inquiring mind wants to know:

Is the raw coil stock a sandwitch of zinc with copper on both sides?


Yes.
They are blanked, deburred, then struck.


I'm having trouble understanding that because the outside diameter of the penny shows no signs of a zinc center layer.

I just gave the OD of a penny a couple of swipes with one of SWMBO's cardboard fingernail sanders and the white zinc then became visible, over what appeared to be the entire thickness of the rim, minus a VERY thin stripe of copper at the very edge which looks to be only a few thou thick.

So, are you saying that the blanking process somehow smears copper over the OD which stays there during the deburring?

(Leaving to have another look at the US Mint's website.)

Whoops! I should have tried suckering you into betting me $20 on the validity of your answer. <G>


I only make bets in beers. I buy a lot of beer. <G>
Well that will teach me to answer the wrong question.
I think my answer applies to quarters, not pennys.


Searching for "plated" got me this from the Horse's mouth*:

************

Following is a brief chronology of the metal composition of the cent coin (penny):

* The composition was pure copper from 1793 to 1837.
* From 1837 to 1857, the cent was made of bronze (95 percent copper, and five percent tin and zinc).
* From 1857, the cent was 88 percent copper and 12 percent nickel, giving the coin a whitish appearance.
* The cent was again bronze (95 percent copper, and five percent tin and zinc) from 1864 to 1962.
(Note: In 1943, the coin's composition was changed to zinc-coated steel. This change was only for the year 1943 and was due to the critical use of copper for the war effort. However, a limited number of copper pennies were minted that year. You can read more about the rare, collectible 1943 copper penny in "What's So Special about the 1943 Copper Penny.")
* In 1962, the cent's tin content, which was quite small, was removed. That made the metal composition of the cent 95 percent copper and 5 percent zinc.
* The alloy remained 95 percent copper and 5 percent zinc until 1982, when the composition was changed to 97.5 percent zinc and 2.5 percent copper (copper-plated zinc). Cents of both compositions appeared in that year.

***********


The way I read this.
It implies, they are plated after being struck ?

PS.
Did you ever build the penny sorter?

'Twas on this page "The Composition of the Cent":

http://tinyurl.com/3dm84

Case closed,



--
Gary A. Gorgen | "From ideas to PRODUCTS"
tunxis@xxxxxxxxxxx | Tunxis Design Inc.
| Cupertino, Ca. 95014
.

Relevant Pages

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