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Mike Byers Mint Error News – 1970-S Proof Washington Quarter Struck on Silver Barber Quarter

Mike Byers Mint Error News - 1970-S Proof Washington Quarter Struck on Silver Barber Quarter

1970-S Proof Washington Quarter Struck on a Silver Barber Quarter


One of Two Known


By Mike Byers for Mint Error News ……
Proof coins are struck by technicians who hand feed the blanks into special presses. They are produced, examined, and packaged using extreme quality control. It is very unusual to find major Proof errors. A few broadstrikes, off-centers, double strikes (in collar), and off-metals have been known to be found in sealed Proof sets. Proof errors are aggressively sought after by many error collectors.

A very small group of Proof errors recently came from a collection that was auctioned by the State of California. The U.S. Secret Service inspected and released this collection to the State of California determining that it was legal to own. The State of California then auctioned the collection and it has been dispersed since the sale.

1970-S Washington quarter planchet "errors".

Proof Washington Quarters struck in 1970 by the San Francisco Mint were clad. This 1970-S Proof Quarter was over-struck on a silver Barber Quarter and is one of two known. This mint error was originally discovered in a group of San Francisco Proof Errors that was auctioned by the State of California. There is some detail on both sides showing the design of the Barber Quarter. This is one of the most famous U.S. Proof Major Mint Errors ever released from the San Francisco Mint.

Along with these famous and enigmatic Washington Quarters from the San Francisco Mint struck in Proof over a U.S. Silver Barber Quarter (1892-1916), there is also a Proof Washington Quarter struck over a 1941 Canada Silver Quarter. These were both featured in a TV interview I did with Fox News. These fascinating errors went “viral” and were featured in USA Today, London’s Daily Mail, AP News, Coin Week, the New York Post, Newsmax, NBC News, Numismatic News, Time Magazine, and on Maria Bartiromo’s TV show.

View more Error Coin News on CoinWeek

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World’s Greatest Mint Errors

The book World’s Greatest Mint Errors is an enjoyable numismatic resource packed full of some of the rarest, most dramatic, and extraordinary errors and die trials ever assembled in one publication. It combines stunning imagery with the most accurate information available to provide anyone interested in mint errors with the latest data on mint error coins from the United States and around the world. Hundreds of spectacular errors are pictured. Each error coin photo is presented in full color and enlarged to enhance the smallest details.

Some of the error coins featured in this book have never been seen by the public before, and each is described in great detail as to the type of error, the assigned grade, rarity, and estimated value. The release of World’s Greatest Mint Errors has only helped to further interest in the field in non-collectors and advanced collectors alike. This book is a must-have for every numismatic library.


Mike Byers
Mike Byers
Mike Byers is the Owner, Publisher and Editor of Mint Error News Magazine and the Mint Error News website that was founded in 2003. In 2009, Mike Byers published his first book, World's Greatest Mint Errors, which received the NLG Award for Best World Coin Book.

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  1. How is this possible this is a fake. Why would the mint have a barber reverse die in inventory. The strike from your photo has wear and does not display a proof finish so the mint discovers the mistake after 2 strikes and stops and yet these 2 pieces somehow escape the mint totally FAKE

  2. It’s possible because human beings inspect these coins. And the worn Barber in the pic was clearly provided for comparison purposes.

  3. I found a coin with the back of a dime on one side… And a penny back on the other side in a brand new roll of dimes from the bank in 2009.. It’s very possible..

  4. im a coin collecting i have coins people will never see i also own the 1970 quarter with 1941 misprint and mint state ,die clad susan B 1889cc just need a guide help


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