1928 Lincoln Wheat Cent - IAM 001
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Description
Designated IAM 001, this 1928 Lincoln wheat cent documents a rare improper alloy mix variety — an error type that occurs when the constituent metals of the planchet are not thoroughly blended before the blank is struck, resulting in a coin with visible streaking, discoloration, or uneven surface characteristics caused by localized concentrations of one metal within the alloy. Lincoln wheat cents of the 1920s were struck on planchets composed of 95% copper and 5% tin and zinc (bronze composition), and improper mixing of these elements during the ingot preparation stage could produce areas where the tin-zinc component was unevenly distributed throughout the copper matrix. Philadelphia struck approximately 134.12 million cents in 1928, using planchets produced from strip metal that was rolled, blanked, and annealed before reaching the coining press. The improper alloy mix would have originated upstream in the production process — during the melting and casting of the bronze alloy before it was rolled into strip — making it a planchet error rather than a die error. Victor David Brenner's wheat cent design, in its nineteenth year of production by 1928, was struck on these occasionally flawed planchets without the Mint's quality control processes catching the metallurgical inconsistency. Improper alloy mix varieties are authenticated by examining the surface under magnification for characteristic streaking patterns, color variations, or unusual surface textures that cannot be attributed to environmental damage, cleaning, or plating. The IAM 001 designation establishes this as the first cataloged improper alloy mix variety for the 1928 cent. Collectors should look for areas of distinctly different color or luster on the coin's surface that follow flow patterns consistent with the metal's movement through the rolling and striking processes.
Attribution History
- Discovered by BrandonDealer
Community & Reference
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