Production Method

Numeral Transplantation

Microscopic analysis of the Unicorn Penny’s surface features reveals characteristic markings that strongly support the conclusion that the date numerals were originally excised from a donor coin or hub and later hand-pressed into a recipient hub.

Examination of UP2—specifically the base of the leftmost date numeral “1” at 1000× magnification—shows a distinctive ridge along the lower portion of the digit (Figure A). The most coherent explanation for this ridge is that it represents a remnant of the numeral’s separation from its donor source. Its presence indicates that, during transfer, the numeral punch descended marginally deeper into the hub surface than the intended working depth of the digit itself.

Further evidence emerges from the way this ridge progressively diminishes along the numeral’s length (Figure B). This tapering is consistent with the punch striking the hub at a slight angle. Comparable ridges occur on all three hand-punched numerals—the leftmost “1,” the “3,” and the rightmost “1.”

At the top of the numeral (Figure C) the ridge fully disappears, showing complete fusion with the coin’s surface. This not only supports the conclusion that the hand-punch entered the incuse hub at an angle but also confirms that a properly hardened working die was ultimately used to strike the coin.

The formation of this ridge almost certainly originated during the extraction of the numeral from its donor coin or hub. To remove a raised digit cleanly, the cutting tool must travel beneath the numeral, penetrating into the surrounding metal so that the digit can be lifted out as a single piece (see illustration below). After removal, the excess metal attached to the underside of the numeral would normally be flattened to create a stable base for mounting onto a punch. Yet minute traces of this excess can remain, forming a subtle ridge around parts of the numeral’s perimeter (see illustration below).

Notably, these ridges are invisible under the types of desk-mounted or handheld magnifying lenses that Mint staff would have used at the time (typically around 10×). Even under modern 40× magnification, the ridges cannot be seen. They only become visible under electronic video microscopes operating at around 1000×.

STEPS 1 & 2