Hobbyists newly infected with the “error bug” quickly encounter the term “uniface.” Translated literally, it means “one face.” In a uniface strike, only one face is die-struck; the other is featureless.

When describing such a coin, more-established collectors will often refer to “the uniface side” or “the uniface surface.” If the term were applied in a logical fashion, one would assume that the uniface side is the one with the die-struck design. However, the hobby perversely designates the featureless side as the uniface side. One way to remember this is to assign a different meaning to the root “uni” and associate the uniface side with the unidentifiable side.

In hobby parlance, a uniface strike is not simply a coin with a single die-struck face. By definition, the featureless face must result from being struck against another planchet. A featureless face that arises from any other cause is designated a “struck-through” error. For example, the off-center 5-cent coin with a smooth, flat obverse featured in the June 24 Collectors’ Clearinghouse would be identified as “100 percent struck-through.”

A representative example of a uniface strike is shown here in the form of a flipover, double-struck 1985 Lincoln cent with an off-center, uniface second strike. The featureless surface is convex, which is a typical development when a planchet blocks the anvil die.

Uniface strikes can appear on the obverse face or the reverse face, and can occur on a first, second or subsequent strike. Occasionally both faces are simultaneously covered by planchets, resulting in a double-uniface or “sandwich” strike.

A second double-struck Lincoln cent displays an off-center second strike with no trace of the obverse design. It’s been replaced by a roughly textured surface that almost certainly reflects contact with something other than a planchet. This coin would therefore be described as having been “struck-through” on the second strike. Although the coin has no die markers that would allow me to determine if both strikes were delivered by the same die pair, it’s very likely that the second strike was delivered in an adjacent striking chamber whose hammer die was covered by a coarse material.

As discussed in the July 30, 2012, column, uniface strikes can be centered or off-center. The former are sometimes struck within the collar (an in-collar uniface strike) or outside the collar (a uniface broadstrike).

Whether centered or off-center, if even a sliver of die-struck design appears on the face that was struck against a planchet, it is not considered to be a uniface strike. The coin is instead considered to have an “indent.” This grammatically objectionable verb-turned-noun forces us to confront another idiosyncratic term invested with a highly specific meaning. For hobbyists, an indent is an impression of another planchet that does not completely block the die face. An indentation from any other source is once again considered a “struck-through” error. An indent constitutes the mate of an off-center uniface strike. Indents can appear on either face and can occur on a first, second or subsequent strike.

Shown here is an off-center Lincoln cent with an “internal” indent on the obverse face. The overlying planchet was aligned along the same axis and in the same direction as the planchet that became this coin, but it protruded outside the striking chamber a little bit more. This positioning exposed a thin strip of the underlying planchet to the direct impact of the hammer (obverse) die.

Use of the terms “uniface” and “indent” overlap when a centered planchet or coin is fully overlapped by another planchet. A centered uniface strike is also often referred to as a “full indent.” A full indent can occur on either face, on the first or second strike, and with the planchet or coin confined by or unconfined by the collar. To make things even more confusing, a full indent on the second strike is more commonly referred to as a die cap.

Is it any wonder that the extensive and confusing lexicon compiled over the years by error researchers is a source of unending frustration for hobbyists?

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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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