Dimes show that elliptical clips may coincide with other clips

Published : 07/02/11
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A coin might deviate from the expected circular outline for many reasons. Most departures from perfect circularity can be traced back to the blanking process. We call such errors “clips” or “incomplete planchets.”

A relatively rare type is the elliptical clip. The defective blank is oval instead of circular. The illustrated undated Roosevelt dime is a typical example.

Many hypotheses have been floated to account for the existence of elliptical clips. The most likely scenario involves a newly punched blank that hangs up in its hole in the coin metal strip. The “hanging blank” is sliced through again by the blanking die when the strip fails to advance properly. A less likely scenario involves a blank getting trapped between the moving strip and the perforated base plate beneath it. Elliptical clips sometimes co-occur with other, more common categories of clip.

Also illustrated this week is an elliptical clip 2007-D Roosevelt dime that nestled against the left side of the collar when it was struck. This side of the ellipse is uninterrupted and shows reeding throughout, although it weakens from 7:00 to 8:00. The right side of the ellipse is interrupted by a large curved clip. Perhaps a blanking die overlapped an already punched portion of the coin metal strip, producing a conventional blank with a curved clip. This blank, however, hung up in its hole in the coin metal strip and was sliced through a third time when the strip failed to advance properly.

The next dime features four clips — three curved and one elliptical. A small curved clip at 3:00 is flanked by two large curved clips. The intact side of the ellipse is on the left and extends from 7:00 to 11:30. Full reeding is seen at 12:00, 2:30, 3:30 and 6:30 points.

The sequence of events leading to this coin may have started with a section of punched strip with holes that were abnormally far apart due to faulty progression of the strip. Three of these holes were then overlapped by the blanking die when the strip again failed to advance properly. A blank with three curved clips was produced, but hung up in its hole. The strip again failed to advance properly, and the triple-clipped blank was sliced through a third time by the blanking die, producing the elliptical clip.

In both curved clips and elliptical clips, the copper core is asymmetrically exposed. In the illustrated quad-clipped dime, the copper core is closer to the reverse face along the convex edges (smooth and reeded), and closer to the obverse face along the concave edges. This reversal of position is expected and likewise present in the double-clipped dime. Each convex edge represents the edge of the blank. Here the bottom clad layer of the strip is smeared over the copper core as the blank is forced through the hole in the perforated base plate of the blanking press. Each concave edge represents a hole, where the top clad layer is smeared over the copper core by the edge of the blanking die.

When combined with other clips, an elliptical clip may be hard to spot, especially if the coin is struck out-of-collar or if the other clips shorten or eliminate the long axis of the ellipse. Expansion of the planchet will distort the elliptical shape, and any loss of weight can be assigned to the other clips.

In like fashion, an elliptical clip might be mistakenly identified if a planchet with two or more overlapping, nonelliptical clips, or a planchet with a single, very large nonelliptical clip, is involved. The planchet — reduced in size along all axes — can move across the striking chamber, even when the collar is deployed. This may leave the normal, convex edge distant from the edge of the striking chamber and the nearby letters cut off. A broadstrike or an off-center strike increases the level of diagnostic uncertainty.

Finally, the delicate tips of a straight-clipped planchet or a crescent-clipped planchet can be forced down into the collar, once again allowing the normal, convex edge to move away from the working face of the collar.

Coin World’s Collectors’ Clearinghouse department does not accept coins or other items for examination without prior permission from News Editor William T. Gibbs. Materials sent to Clearinghouse without prior permission will be returned unexamined. Please address all Clearinghouse inquiries to cweditor@coinworld.com or to (800) 673-8311, Ext. 172.

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