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Alaska quarter die flow lines dramatic

A.G. Meredith of North Carolina sent in a 2008-P Alaska state quarter with a rather prominent example of an otherwise common effect seen on a large percentage of coins struck at the United States Mint’s coining facilites. The coin was obviously struck with a reverse die that was in a very-late-die-state where pebbly “orange peel” surfaces and very heavy die flow lines dominate.

This itself is nothing unusual. The U.S. Mint has a tendency to use business strike dies (those intended to manufacture circulation coinage) to the very end of their life. A pair of dies set into a press in the morning of a typical day may not even last through the day before they need to be replaced and most of the coins from that set of dies will range from the mid-to-late die states.

The average life of a die used for the states quarter series is 250,000 strikes. Then they need to be replaced due to the effects described above or other concerns such as die cracks or breaks.

Though we do see it from time to time, what is unusual about this coin, is the fact that it appears to have been struck on a tarnished or otherwise stained planchet, which intensified the appearance of the die flow lines. Die flow lines are typically strongest nearest the rim and along with the planchet discoloration; the result is an interesting starburst effect that is easily seen with the naked eye.
In seeking out a second opinion for what might have caused the darkening of the die flow lines, I sent images of the coin to Sean Moffatt of Moffett & Co., a private Mint located in Eureka Springs, Ark. Moffatt was operations manager of Hoffman Mint of Carmel, Calif., for 19 years until it closed and he started his own minting operation in 2007.

According to Moffatt: “The die has heavy, almost unnatural flow lines. But they are flow lines.The discoloration is from anybody’s guess. Whatever caused the discoloration took the path of least resistance, into the image devices and then in the flow lines that were worn into the die.

“The metal near the outside diameter of the coin moves at the greatest velocity during coining. This is due obviously to its close proximity to the outside diameter and also typically there are no large image devices to suck up metal in another direction, so the metal has to flow outward as the blank runs out to the collar.

“It appears the mystery material collected in the image devices, (lettering, etc.), as there was lower pressure in these areas and as the metal began to fill the devices it squeezed the mystery substance out at a very high velocity and pressure. Whether or not the mystery substance caused the flow lines I cannot say, but it surely moved through the flow lines when it was forced to as the pressure was lesser there than on the smooth fields.”


Ken Potter is the official attributer of world doubled dies for the Combined Organizations of Numismatic Error Collectors of America and for the National Collectors Association of Die Doubling.  He also privately lists other collectible variety types on both U.S. and world coins in the Variety Coin Register.  He is a regular columnist in Numismatic News’ sister publication, World Coin News, where he pens the Visiting Varieties column.  More information on either of the clubs or how to get a coin listed in the Variety Coin Register may be obtained by sending a long, self-addressed envelope with 61 cents postage to P.O. Box 760232, Lathrup Village, MI 48076, or by contacting him via e-mail at KPotter256@aol.com. An educational image gallery may be viewed on his Web site at www.koinpro.com.

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