RIDB-1c-2006D-01 Retained Interior Die Break

Description

As the first cataloged retained interior die break for the 2006-D Lincoln Memorial Cent, RIDB-1c-2006D-01 documents an interior die fracture on a Denver Mint working die from the final era of the Memorial reverse, which would be replaced by Bicentennial designs in 2009 followed by the Union Shield reverse in 2010. A retained interior die break forms when a fragment of the die face separates from the surrounding steel at an interior location and remains in place, continuing to strike coins with a raised, blob-like area of displaced metal sitting entirely within the normal design field. This distinguishes RIDBs from the more common rim cuds. Interior fractures arise from stress concentrations caused by metallurgical imperfections, accumulated fatigue from millions of strikes, or residual stresses from hubbing. The 2006-D cent was produced in quantities typical of early twenty-first-century Denver output, and die breakage varieties from this period document that even modern die steel and manufacturing techniques cannot eliminate catastrophic failures entirely.

Attribution History

• Discovered by Mike Durney
• Cross reference number: none. 03/16/2019.
• Expert attribution by Cuds on Coins

External References