US Coins

Errors & Varieties: Long-known abrasion doubling fails to survive close scrutiny

One of the rarest and most controversial forms of doubling is abrasion doubling. As originally defined by Alan Herbert, two forms were identified: “inside abraded die doubling” and “outside abraded die doubling.”

Herbert’s description of inside abraded die doubling establishes it as a type of intentional retouching in which an abrasive (instead of an engraving tool) is used to modify recessed design elements in the face of a working die. Retouching is a rare but well-documented phenomenon, with most cases involving proof dies.

Unfortunately, the coins Herbert used to illustrate inside abraded die doubling are emphatically not cases of intentional retouching; they are garden-variety examples of die deterioration doubling.

For example, the Jefferson 5-cent coin pictured on page 174 of the 6th edition of Herbert’s Official Price Guide to Mint Errors shows the irregular expansion of peripheral letters typical of this common form of doubling. As a result, inside abraded die doubling can be discarded as a useful concept.

Outside abraded die doubling suffers from similar problems. Herbert defines this form of doubling as an occasional side effect of intentional die abrasion performed to remove light clash marks and other forms of die damage.

But the coin he chose to illustrate the category (page 175) is a 1955 Lincoln cent with a “poorman’s double die.” The outside of the last digit shows hazy doubling that is widely recognized as a manifestation of die deterioration. Similar doubling affects the terminal digit of 1947, 1948, and 1953 cents.

From this point on I’ll simply refer to outside abraded die doubling as simply “abrasion doubling,” because the two terms have become synonymous within the hobby.

I’ve always been skeptical of abrasion doubling because I’ve never found it in association with clear evidence of intentional die abrasion.

Common signs of intentional die abrasion include the presence of profuse die scratches, attenuated (thinned) design elements, and the loss of low-lying areas of design.

Of the thousands of coins I’ve examined that were struck by heavily abraded dies, not a single one showed anything that could be considered “abrasion doubling.”

Despite the absence of a smoking gun, I held out the possibility that abrasion doubling might constitute a legitimate, albeit rare form of doubling.

John Wexler published images of several Lincoln cents with intriguing patterns of doubling at, Wexler’s website.

I recently acquired an example of what is arguably the most dramatic case of abrasion doubling depicted in Wexler’s gallery, a 1971 Lincoln cent (see photos). It is considered by some to be a doubled die and for those who operate under that assumption it is classified as FS-1c-030.7 in The Cherrypickers’ Guide to Rare Die Varieties (fourth edition).

The specimen I purchased shows a middle die state, i.e., one characterized by an average state of die wear.

Strong doubling occurs north of the last two letters of LIBERTY and the middle two digits of the date.

The coin shows no independent evidence of intentional die abrasion. It has no die scratches, the width of letters and numbers is normal, and areas of low relief remain intact.

Many of the extra elements have an irregular “beaded” appearance when viewed under high magnification.

Whether such an odd appearance should be considered a hallmark of abrasion doubling is unclear. At the very least, the beaded appearance seems inconsistent with its proposed status as a doubled die.

I find compelling evidence that the doubling is due to die deterioration. Extending from the back margin of Lincoln’s coat are numerous tiny spiky extensions.

Elsewhere in and around Lincoln’s bust are tiny bumps occurring singly or in clusters (see photos). The spikes and bumps are not the result of intentional abrasion but represent a peculiar manifestation of somewhat accelerated die deterioration.

The clusters of bumps share the same characteristics as the beaded extra elements.

When the most dramatic example of abrasion doubling turns out to be just another case of die deterioration doubling, one must question the validity of the entire category.

Until more persuasive evidence is presented, I will henceforth consider abrasion doubling a myth.

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