Lamination (LAM)

A lamination error occurs when a layer of a coin's metal peels, flakes, or separates from the planchet surface. The flaking, peeling and cracking are generally attributed to impurities in the alloy, which leave the metal with horizontal planes of weakness along which it separates (Error-Ref). The layers can split apart before, during or after the strike. Lamination errors range from tiny surface flakes to dramatic separations that expose large areas of the coin's interior metal.

How Does It Happen?

Lamination errors originate during the production of metal strip, long before the blank is punched or the coin is struck. The defect is built into the raw material.

The causes include:

• Impurities in the alloy: Foreign material in the metal does not bond with the metal around it. When the metal is rolled into thin strip, these flaws are flattened into thin planes of weakness running parallel to the strip's surface, and those planes become the fault lines for later separation.

• Clad coins are a special case: On clad dimes, quarters and half dollars, the copper-nickel outer layers are already very thin, so a lamination inside a clad layer is unusual, though it does occur. A true lamination on a clad coin does not expose the copper core. When a clad layer comes away and the copper core shows, the error is a partial or missing clad layer, a different planchet error (Error-Ref).

The lamination can occur at any depth within the metal. Surface laminations involve a thin outer layer; deep laminations can split the planchet nearly in half. The separation can happen before striking (the coin is struck with the lamination already present), during striking (the pressure of the strike opens the weak plane), or after striking (the latent weakness fails during handling, rolling machine processing, or circulation).

How to Identify a Lamination

Lamination errors have distinctive visual characteristics:

• Retained flap: The most dramatic presentation. A layer of metal has partially peeled away from the surface but remains attached at one edge, creating a raised flap. The flap can be folded back to reveal the rough, exposed interior metal beneath it. The full scope of the error is visible.

• Missing layer: The peeled layer has fully separated and fallen away. The coin shows a recessed, rough, irregularly shaped area where the surface metal is absent. The exposed interior has a different texture from the normal struck surface -- typically porous, granular, or fibrous.

• Surface crack or split: The lamination has begun but not fully separated. A crack or hairline split is visible on the surface, often with slightly raised or displaced edges. The metal on either side of the crack is at slightly different levels.

• Blister or bubble: A trapped gas pocket creates a dome-shaped raised area on the coin's surface. The blister has not yet ruptured, but the metal above the gas pocket is clearly separated from the metal below it. Striking pressure sometimes flattens blisters partially, creating an irregular raised zone.

• Edge lamination: The separation is visible on the coin's edge as a split or gap in the metal. Edge laminations can extend partway around the coin's circumference.

Key Diagnostics

Lamination vs. Post-Strike Damage

Genuine laminations are sometimes confused with post-strike scrapes, gouges, or corrosion. The key differences:

• Lamination plane is parallel to the coin's surface: The separation follows the direction the metal was rolled. Post-strike gouges cut at angles through the metal.
• Exposed interior texture: Lamination exposes raw internal metal with a distinctive granular or crystalline texture. Scrapes and gouges leave smooth, polished trenches.
• No tool marks: Laminations have organic, irregular boundaries. Mechanical damage shows directional scratches, sharp edges, or repetitive patterns from the damaging tool.

Notable Examples

Clad Quarter Laminations

Error-Ref illustrates a 2002-P Indiana State quarter on which a small piece of surface metal has peeled off and fallen away, with a second, still-attached area of lifting metal beside it. Because the lamination lies within the copper-nickel layer, the copper core is not exposed. A clad coin showing bare copper core has a missing or partial clad layer instead.

Wartime Silver Nickels

The 1942-1945 wartime Jefferson nickels, struck in an alloy of copper, silver and manganese, are often cited as prone to laminations. A numismatic dictionary entry describes them as particularly susceptible to alloy imperfections, and collectors report laminations on these coins as common (search).

Collecting Tips

• Retained flaps show the whole error: Laminations with a retained flap, the peeled layer still attached, show where the layer came from. A coin whose flap has broken off shows only the missing area.
• Size: Laminations range from small flakes to separations covering much of a face. Describe the affected area when you record one.
• Both sides can be affected: Check both the obverse and reverse. A coin can have laminations on both sides if the strip had flaws at multiple depths.
• Protect the flap: If you acquire a lamination with a retained flap, handle the coin carefully. The flap is fragile and can break off with rough handling. Use appropriate holders and avoid sliding the coin across surfaces.
• Don't confuse it with a missing clad layer: On a clad coin, exposed copper means a clad layer error, not a lamination.
• Authentication: PCGS and NGC certify lamination errors, which separates them from post-mint scrapes and corrosion.