Repunched Mint Marks (RPM): What They Are and How to Find One

Repunched Mint Marks: A Collector-Favorite Variety

A repunched mint mark (RPM) occurs when the mint mark punch is impressed into the die more than once, with the second impression slightly offset from the first. The result is a coin that shows two (or more) overlapping mint mark impressions — a clear sign that the die was punched, repositioned, and punched again.

RPMs are among the most collectible die varieties because they're relatively common (making them findable), easy to attribute once you know what to look for, and well-documented across many denominations and years.

How RPMs Were Created

Through 1989, mint marks were added to dies by hand using a small steel punch. A Mint employee would position the punch in the correct location and strike it with a hammer to impress the mint mark (D, S, or O) into the die. If the first impression wasn't positioned correctly or wasn't deep enough, the punch would be repositioned and struck again.

This manual process meant that the second punch could be offset in any direction — north, south, east, west, or at an angle. The direction and degree of the offset is what distinguishes one RPM from another.

Note: Starting in 1990, mint marks were added directly to the master die (hub) rather than to individual working dies. This eliminated the possibility of new RPMs, making 1989 the last year an RPM can occur and pre-1990 coins the hunting ground for RPM collectors.

What to Look For

Under 5x-10x magnification, examine the mint mark area for signs of a second impression:

• Secondary image — A ghost-like partial impression of the mint mark letter visible near the primary impression
• Thickened edges — One side of the mint mark may appear thicker than the other, indicating overlap
• Serifs or notches — Parts of the secondary impression that extend beyond the primary mint mark's outline

RPM vs. Normal Mint Mark

A normal mint mark shows a single, clean impression with uniform edges:

Best Series for Hunting RPMs

RPMs are most commonly found on:

• Lincoln cents (1909-1989) — The largest volume series with hand-punched mint marks
• Jefferson nickels (1938-1989)
• Roosevelt dimes (1946-1989)
• Washington quarters (1932-1989)

NumisDex catalogs thousands of RPM varieties across all denominations. Browse them in the RPM catalog to familiarize yourself with what different RPMs look like — then start checking your own coins.