1990 UFO Variety WUFO-001

Description

One of the most genuinely puzzling varieties in the Lincoln Memorial cent series, WUFO-001 on the 1990 cent earned its Unidentified Fascinating Oddity classification after prominent numismatic analyst Mike Diamond — writing in his Collectors Clearinghouse column for Coin World — systematically eliminated every conventional explanation for the raised circular feature found on the coin's surface. Diamond's analysis ruled out a plating blister, noting the feature was not a hollow dome of separated copper plating. It was not a solid zinc dome pushed up from the substrate. It was not a die chip, which would produce a different surface texture. It was not a die bleb — a raised bump caused by corrosion or pitting of the die face. It was not a Rockwell test mark, the circular indentation left by hardness testing equipment. And it did not match any recognized form of accidental die damage. What Diamond concluded was that the feature originated from "a tiny indentation in the die face" that transferred as a raised element on the struck coin, with a "perfectly circular shape" that defied attribution to any known die manufacturing process or production anomaly. The Wexler Team assigned it the UFO listing number WUFO-001, acknowledging that despite expert examination, the variety remains an unexplained curiosity — a genuine mystery in a field where most anomalies yield to careful analysis. Struck at Philadelphia on copper-plated zinc planchets composed of 97.5% zinc and 2.5% copper, weighing 2.5 grams and measuring 19mm.

Attribution History

• Discovered by Kenneth R. Simpson Cross References: None known Comments: Since this crazy “variety” falls outside my realm of expertise, Mr. Simpson contacted Mike Diamond who writes the Collectors Clearinghouse column for Coin World and is quite an expert at both errors and die varieties. Mr. Diamond’s analysis follows: “Contrary to my expectations, it does not appear to be a plating blister, a solid dome of swollen corroded zinc, a die chip, or a die bleb (die erosion pit). It really does appear to be a tiny indentation in the die face. As to what caused it, I can’t speculate. It’s too small and in the wrong location to be a Rockwell test mark. Rockwell test marks should be out in the middle of the field, since impressing one close to a die recess will alter the reading. It could represent accidental die damage, but its perfectly circular shape would be unusual for such an error.” Mr. Diamond further comments that “It will probably be filed away as an unexplained curiosity.” Based on this analysis I feel it definitely deserves a UFO listing number.
• None known Comments: Since this crazy “variety” falls outside my realm of expertise, Mr. Simpson contacted Mike Diamond who writes the Collectors Clearinghouse column for Coin World and is quite an expert at both errors and die varieties. Mr. Diamond’s analysis follows: “Contrary to my expectations, it does not appear to be a plating blister, a solid dome of swollen corroded zinc, a die chip, or a die bleb (die erosion pit). It really does appear to be a tiny indentation in the die face. As to what caused it, I can’t speculate. It’s too small and in the wrong location to be a Rockwell test mark. Rockwell test marks should be out in the middle of the field, since impressing one close to a die recess will alter the reading. It could represent accidental die damage, but its perfectly circular shape would be unusual for such an error.” Mr. Diamond further comments that “It will probably be filed away as an unexplained curiosity.” Based on this analysis I feel it definitely deserves a UFO listing number.; Wexler Variety ID: 1990 1¢ WUFO-001
• Expert attribution by Wexler Team

External References