"Oh, No It Ain't ...!!"
#35

Is My Coin a Wrong-Planchet Strike?
Or is it an 'Acid Coin'?
by Ken Potter -- NLG
11/11/2008

Here is a 1953 Jefferson nickel that was soaked in acid.

    One of the most frequent questions that error-variety coin examiners receive revolves around what we call "acid coins."  These are coins that for one reason or another were soaked in acid and as a result had their diameter, thickness and weight reduced.  Many are less than half of their original weight yet because the acid erodes the surface somewhat evenly, many will retain enough of their original design to be recognizable.  They are often presented as great rarities that the finders are fairly certain represent some sort of off-metal or wrong-planchet error; a coin that was perhaps minted on a foreign planchet.  Sometimes the theory is that they were struck on some sort of experimental planchet from a long-forgotten test project with the finder now holding the only piece extant. However, the bad news is that most often these finds are not what their finders hoped them to be.
    Of course, there are genuine off-metal and wrong-planchet strikes and there are genuine metallurgical trial strikes but in the vast majority of cases that a coin is described as being of reduced diameter, thickness and weight, it turns out to be an acid coin.  Where do they come from?  Well, some are outright intentional alterations made from genuine coins to defraud gullible buyers.  However, I believe most are the result of coins that have been improperly cleaned in acid based coin cleaners known as "coin dips."  Even though users are instructed to just swish a coin around in the dip for a few seconds and to then rinse well and dry, some folks think that more is better especially when a tough stain does not respond to the dip within the first few seconds.  They leave the coin in the dip with the intent of returning a few minuets later and then forget that it is there.  Several days or a week later the coin is remembered and presto we have our acid coin!
    The physical differences between acid coins and genuine off metal and wrong planchet errors are glaring but the main characteristics of an acid coin are best learned by simple observation.  Look for designs that seem to be fading into the field, thinned out lettering and pebbly or otherwise eroded surfaces.  Many will be so thin that they will sound tinny when dropped on a table top. 

Here is a 1915-D cent that was soaked in acid.

This 194X cent was soaked in acid so long that it is barely recognizable as a cent.

For this 1976-D Bicentennial quarter, the outer clad layers most probably separated from the inner core during the
 acid bath.  The coin then ended up as three separate "coins" with this copper core maintaining much of the original design.

Here is a look at a genuine 1979 Jefferson nickel struck on a Lincoln cent planchet.

    History of the "Oh, No It Ain't ...!!" column:  A number of years ago, CONECA member, Bill Fivaz penned a popular long-running series entitled, "Oh, No It Ain't ...!!"  It was published in the CONECA Errorscope for 26 consecutive issues from the March 1991 issue through the July/August 1994 issue.  His focus was on a variety of different coins that at first glance may have fooled many collectors into believing they were legitimate error coins.  It included such items as faked clips, double strikes and brockages; plugged coins, reeded blanks, Mint/Proof Set Sealing Device damage, "jumbo coins" (from hammering), etc.
    When Bill finally ended the series he indicated that if there was anybody who wanted to carry it on that it was open to them.  Later, when I mentioned the column to him in casual conversation, he repeated his offer and suggested that if I was interested in reviving the series -- to feel free.  That offer was made eight or nine years ago and since then I've entertained the idea, off and on, many times.
    The clincher was the CONECA Membership Survey that was sent out in 2003.  In it we asked members for their likes/dislikes and suggestions of what they'd like to see in the Errorscope or on the web site.  Respondents ranked a column such as this one right at the top of the list.  So be it!  The revived "Oh, No It Ain't ...!!" column will continue on from where Bill left off.  I hope you enjoy!   Ken Potter 03/11/04.

Opinions expressed in articles or other features posted on the CONECA web site do not necessarily represent official CONECA policy or those of it's officers.  The act of submitting material shall constitute an expressed warranty by the contributor that the material is original; if not, the source and permission must be provided.

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