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Mike Byers Mint Error News – Unique 1970-S Proof Washington Quarter Overstruck on Canadian Quarter

King George V (1911-1936) Mint Error




By Mike Byers for Mint Error News ……
This unique 1970-S Proof Quarter mint error from the United States was overstruck on a Canadian Quarter that circulated during the reign of King George V from 1911-1936. It was authenticated and certified by NGC as PR64. This was most likely from the group of San Francisco Proof Mint Errors that was auctioned by the State of California.

mint error

There is a significant amount of detail on both sides showing the design of the Canadian Quarter. This is a flip-over where the obverse design of the Canadian Quarter which shows the portrait of King George V is visible underneath the U.S. Quarter reverse design.

mint errorThe reverse design of the Canadian Quarter showing the wreath is visible underneath the U.S. Quarter obverse design. This is one of the most fascinating and intriguing Proof mint errors ever discovered.

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 United States 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.

mint error

A different 1970-S Proof Quarter from the United States was overstruck on a 1941 Quarter from Canada. It was authenticated and certified by NGC as PR65. The unique 1970-S Proof Washington Quarter overstruck on a 1941 Canadian Quarter is the only one known with King George VI. It went viral and was featured on Fox News, USA Today, and countless other publications.

View more Error Coins 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 Byershttps://minterrornews.com/
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. My 2000 10 coin proof set contains 2 wonderful error coins sealed in OGP. One quarter and the cent !
    This set has NOT been graded
    I always hear about this quality control being so strict yet I am baffled on how this set got passed Q.C.


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