planchets

Planchets are blank metal disks used in coin production, also known as blanks or flans in numismatics. They serve as the substrate that receives the coin’s design when struck by the dies. While round planchets are standard, non-circular shapes have occasionally been used for commemorative issues.

Materials and preparation: Planchets are punched from rolled metal stock to prescribed weights and diameters. Common base metals include copper, nickel, zinc, and aluminum, with alloys such as cupronickel, brass, and bronze used for various coins. Precious metal planchets are employed for bullion or special editions. After punching, planchets are cleaned, descaled, and annealed to achieve a consistent softness and surface quality. They are weighed and inspected for defects before entering the coining operation.

Manufacturing and use: In a mint, planchets are fed between coin dies and struck under high pressure to imprint the obverse and reverse designs in a single or multiple strikes. The edge of the finished coin may be plain, reeded, or feature edge lettering, depending on the coin’s specification. Planchets are then counted, sorted, and prepared for packaging and distribution.

Variations and issues: Planchets vary by composition and thickness to match the intended coin. Defects related to planchets—such as clipped planchets, off-center strikes, laminations, or cracks—can produce errors that are of interest to collectors. Clipped planchets result from excess trimming or mis-sized blanks, leaving a portion of the edge missing on the final coin.

See also: coin minting, coin blank, numismatics.