By Ken Potter - I reported upon a Spiked Head die crack on a proof 2007-S Thomas Jefferson Presidential dollar in the Nov. 13, 2007, issue of Numismatic News. What I did not say was that it was actually just one of several Spiked Heads found on proof coins submitted to me in the past year and a half.

New to the list of significant die cracks on proof coins are 12 examples dated 1998-S, 1999-S, 2000-S, 2005-S and 2006-S, spanning all denominations from nickels through a single Sacagawea dollar. The “list” was originally started with a Spiked Head 2002-S silver Kennedy half dollar that headlined the April 15, 2003, issue of NN. This coin prompted a long string of finds that followed as folks began to check other denominations and dates closer.

The 10-part series of reports ran intermittently with the last appearing in the June 14, 2005, issue up until my recent Jefferson dollar story. Read Full Article

After 47 years of ownership, Edgar Murphy of South Carolina decided finally to find out exactly what kind of error he’d purchased as a youth back in 1960. He contacted me by e-mail and made arrangements to send his error coin in for examination.

It turned out to be a rather neat 1954-S Roosevelt dime that was double struck in-collar with the second strike flipped over, what is referred to simply as a “Double Struck Flip Over” in error collector parlance.

Portions of the reverse show through the obverse design and the portions obverse show through the reverse design. The effect is a composite of both designs with the second strike dominating.

An interesting diagnostic of in-collar double strikes is that more than 99 percent of them fail to be forced all the way back down into the collar for the second strike. This is due to very slight expansion of the coin after it is ejected from the collar; after ejection it is too large to fit back in to the collar and needs to be forced in by the strike. Read Full Story

Paul Kmiotek of New York was in for a big surprise when he opened the 2007 state quarter proof set his in-laws gave him on his birthday. The last thing he expected to find was a major minting error.

When he slid the set out of the box, he saw that the lower right corner of the case was jammed partially open by the high flange of a misstruck 2007-S Wyoming state quarter.

At first he didn’t notice the error and tried to snap the case back closed, but the high flange that was cupped upward from obverse forced it to spring back open. He then noticed the “problem” and decided to contact Numismatic News about his find. The report was forwarded to me and I then consulted with a pool of experts to see what they thought.

Fred Weinberg of Encino, Calif., said, “I’d call it a Close Overlapped Double Strike, Cupped, with a Tilted Partial Collar. As a proof states quarter, I’d estimate it at $1,500-$1,800 retail value.” Read Full Story