Expert: Ronald Fern - 8/31/2011

Question
Mr. Fern, I have found a 1999 D Pennsylvania state quarter error. The obverse is normal, the reverse is missing the "silver" clad and is only showing copper.  Keep it or use it to pay for a car wash?
Respectfully, Scott

Answer
Hi Scott:

Thanks for the opportunity to answer your question. State quarter errors, especially major ones, are very collectible and some quite valuable.

With odd or unusual coins, you always need to provide as much information as possible or photos, to help pinpoint what you may have. The key to being able to establish what you have has to do with the weight, diameter and thickness of your piece. A normal quarter weighs 5.67 grams, is 24.26 mm in diameter, and is 1.75 mm in thickness. You can check if it has the proper characteristics.

For more information, see: http://en.wikipedia.org/wiki/Quarter_(United_States_coin)

You may have what is known as an "Unfinished Planchet" or "Missing Clad Layer(s)" error. It may also be a copper plated normal coin. If this is the case, the quarter should weigh the same or a little more than a regular quarter. It would be impossible to determine if it was done in or outside the mint.

In the minting process, the blank that coins are minted from are cut from long strips of metal made like a sandwich with a copper nickel alloy for the outer layers and the center metal is made of just copper. This is what you see on the edge of normal dime coins. As the strips reach the end they are not completely plated, either on one side or both. Then when the blank planchets are cut out of the strips, they will be missing the silver looking copper nickel layer on one or both sides.

These unfinished planchets can continue undetected, along the mechanized minting process, to the coin press, and have the design stamped into them -- giving you what looks like a normal coin, except for the copper color on one side or both.

For an illustrated explanation of the minting process, you can go to the U.S. Mint's website :
http://www.usmint.gov/faqs/circulating_coins/index.cfm?action=coins

This can happen more often than you think, because with the billions of coins produced every year, it is impossible to visually inspect every coin, and the mechanical processes to sort out error coins will not detect this error. It is entirely random wether the blank missing the clad layer would fall into the die chamber with the front or back side missing the clad.

Its value is $3-$5 (plated) to $250-$400 (missing clad layer), depending on what type of error it is.

You may want to check Ebay listings under US coins in the error and the quarter category to see if your coin is listed and what it is going for.

You may also want to check out these links on error coin values:
http://www.coinsite.com/html/USErrorPrices.asp
http://www.minterrornews.com/priceguide.html

If you live close to a local shop, they should offer an opinion as to the value at no charge. Always try and get at least two opinions and try and deal with PNG dealers if possible. If you should decide to sell your items to a dealer, remember they will offer about 50% to 60% of the retail value. Here's a link to find one in your area: http://www.pngdealers.com/dealersearch.php

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Thank You and Good Luck in your collecting.