A Rim Cud (RCU) is a coin variety in the "Die Damage Family" group. It results from an anomaly during die wear or physical damage at the United States Mint. Coins exhibiting this error carry distinct diagnostic markers that distinguish them from normal strikes and are actively collected by error and variety specialists.

How does a Rim Cud occur?

A Rim Cud occurs due to physical damage, stress fractures, or progressive wear on the die surface during production runs. Once the affected die enters a production run, every coin it strikes carries the same diagnostic markers until the die is retired or replaced.

How do I identify a Rim Cud?

Examine the coin for raised lines, lumps, or missing design elements that correspond to damage on the die. These features appear in the same location on every coin struck by that die. For confirmed Rim Cud varieties, cross-reference the coin against the NumisDex catalog entry which lists known die markers and attribution details.

Are Rim Cud coins valuable?

Value depends on the specific die variety, the prominence of the error, the coin's grade, and collector demand. Some Rim Cud varieties are common and modestly priced, while others — especially early die states or dramatic examples — can command significant premiums. Check recent auction records and price guides for the specific variety.

Where can I find Rim Cud varieties in the NumisDex catalog?

You can browse all known Rim Cud varieties on NumisDex by visiting the catalog and filtering by the "Rim Cud" error type. Each listing includes attribution details, die markers, and images when available.

Rim Cud (RCU)

A rim cud records the loss of part of the die's rim gutter. On the coin it shows as a raised break in the design rim that follows the rim's course exactly. That is Error-Ref's definition, and it is the one this catalog uses. Error-Ref files rim cuds among die breaks, beside cuds.

In plain terms: a rim cud is a raised bump that sits in the rim and follows its curve. It does not spread into the field, and it does not cover lettering, the date or the portrait. Location notes such as "at 2:30, beside the wheat stalk" tell you where along the rim to look, not what the rim cud covers.

What the Rim Gutter Is

On a coin, the rim is raised. On the die that strikes it, the rim is the opposite: a recessed groove running around the edge of the die face, called the rim gutter. Planchet metal is pushed into that groove during the strike, and it comes out as the coin's raised rim. A rim cud records a die that has lost part of that gutter. Every coin the die strikes afterwards carries the same raised interruption at the same place on the rim.

Rim Cud vs. Cud vs. Pre-Cud

These are separate die failures, and a rim cud is not a small cud.

	Rim Cud	Cud	Pre-Cud
What failed on the die	Part of the rim gutter was lost	A piece of the die face broke away at the edge	A rim-to-rim crack enclosing a section at the edge; nothing has broken free or moved
What the coin shows	A raised interruption in the rim that tracks the rim	A featureless raised area that can extend from the rim into the field and design	A raised crack line, with the design normal on both sides
Design affected	None; it stays in the rim	Can cover lettering, date and devices	None; the design is unchanged

A coin can carry a rim cud and a pre-cud or a cud at the same time, from the same die or from its partner die. They are still two failures, not two stages of one break. See Cud, Pre-Cud and Retained Cud.

How to Identify a Rim Cud

It is in the rim. The raised area sits on the design rim itself. If it runs into the field, the variety is a cud, not a rim cud.
It follows the curve. The interruption tracks the course of the rim rather than bulging inward in a blob.
It repeats. It is a die feature, so every coin from that die in that state shows it in the same position. Compare against other examples of the attribution before calling a raised rim area a rim cud. Post-strike rim damage does not repeat from coin to coin.
Note the side and clock position. Record the obverse or reverse and the clock position, e.g. "reverse, 3:00 to 4:00", so the variety can be matched to a catalog entry.

How Rim Cuds Are Cataloged

Cuds on Coins, the main reference for die breaks, uses the same CU- designator for rim cuds and cuds and lists them on the same pages. Its entries distinguish the two in the label printed beside the code, for example "CU-1c-1919S-12R Rim Cud". A trailing R in the number means the reverse die, not "rim". NumisDex files these entries under Rim Cud wherever Cuds on Coins labels them that way. Until October 2026 they were filed under Cud.

Some dates have many: Cuds on Coins lists twenty rim cud files for the 1919-S Lincoln cent (CU-1c-1919S-01R through -20).

Collecting Tips

Look along the rim, not the field. Rim cuds are easy to pass over because the design is untouched. Rotate the coin under a light and follow the rim all the way round.
Check the attribution, not just the bump. A rim cud is cataloged by its die. Match the side and clock position to the catalog entry before attributing.
Don't confuse it with a cud. A raised area that leaves the rim and covers design is a cud. Labeling it correctly matters for attribution.

Rim Cud