US Coins

Impressive Proof errors head to auction at Heritage

While major auctions associated with the March Whitman Baltimore Expo and the April Central States Numismatic Society’s convention have been moved, online auctions are proceeding as scheduled, including Heritage’s April 15 online error coin auction.

Perhaps most impressive in the sale is a triple-struck 1973-S Kennedy half dollar, graded Proof 64 Cameo by Numismatic Guaranty Corp. Evidence of all three strikes is visible on both sides, and the date and Mint mark remain clear from the final strike.

Heritage writes, “This kind of error is unusual enough when it occurs with circulation strike coins, but the San Francisco Mint struck only cents and proof coins in 1973, meaning that this half somehow made it through rigorous quality control into a proof set!”

Another impressive error on a Proof 1973-S Kennedy half dollar also leads one to ask, “How’d that get out of the Mint?” It’s tough to imagine it sliding out unnoticed in a 1973-S Proof set.

It is graded Proof 63 Deep Cameo by Professional Coin Grading Service who classifies it as a “Close Overlap Double-Strike.” Heritage calls it, “A spectacular modern error, especially on a proof coin, showing a perfectly aligned, perfectly centered double strike with the second strike producing a second, elevated reeded edge around the reverse, while the first strike’s edge expands beneath the collar.”

It has a diameter larger than a typical Kennedy half dollar and is certainly a conversation starter.

Wrong planchet errors

The online auction is rich in wrong planchet errors that occur when a coin is struck on a planchet intended for a different denomination. In 1943 the U.S. Mint switched to a zinc-plated steel planchet for its cents to conserve bronze for World War II efforts, and some cent examples were accidentally struck on 90 percent silver dime planchets. The mistake is understandable, given that the color of both is similar, in contrast to bronze, and while 1943 Lincoln cents struck on bronze planchets were also struck and are rare and extremely expensive, 1943 cents on dime planchets are more available and therefore more affordable.

Heritage’s offering is graded Extremely Fine 40 by PCGS, and at first glance, it appears to be a “normal” 1943 Lincoln cent, which explains the 20 points of wear. As Heritage explains, “It is easy to see how a similarly sized, similar-color silver dime planchet would have been unnoticed if it fell in with the steel cent planchets prior to coinage.”

On closer observation, one notices that some legends merge with the rims, since the dime planchet is smaller than the cent planchet.

Also noteworthy is a 1977-S Jefferson 5-cent piece struck on a planchet intended for a bronze cent, graded Proof 67 Cameo red by PCGS. Like the 1943 Lincoln cent struck on a dime planchet, the subject coin is missing a bit of detail at the rims due to the smaller-sized planchet. Heritage observes, “Copper-pink surfaces are deeply mirrored and show no distracting abrasions, and cameo contrast is strong on both sides,” adding that it was, “Struck with an almost 180 degree die rotation.”

Connect with Coin World:  

Sign up for our free eNewsletter
Access our Dealer Directory  
Like us on Facebook  
Follow us on Twitter

Community Comments