Amid the nationwide mobilization effort for the Second World War, the United States Mint was forced to explore using new materials for its low-denomination coins as nickel and copper supplies were diverted to war production. This led the mint to replace the normal composition of the five-cent nickel (which was 75% copper and 25% nickel) with what has become known as "war nickels" made from an alloy of 35% silver, 56% copper, and 9% manganese between 1942 and 1945. Production of the standard copper-nickel coins resumed after the war.
In addition to altering the composition of the Jefferson nickel, the U.S. Mint also experimented with a variety of materials for the Lincoln cent. This culminated in the mint issuing pennies struck from zinc-coated steel in 1943. Some cents from 1943 and 1944 are even known to have been struck from silver by error, according to Whitman's official Red Book.
Interestingly, before the production of steel pennies was settled upon, the mint even had trial patterns made from glass! The first intact glass cent pattern has just recently been discovered and is now certified by Professional Coin Grading Service (PCGS).
Why Is There a Glass Cent?
To deal with the wartime shortage of copper, a whole slew of different materials were considered for the one-cent coin. Most of them were plastics. Independent contractors were hired by the mint to produce an acceptable replacement cent—the strangest of which involved the use of glass as a substitute for the common coinage metals.
In order to make a penny from glass, the Blue Ridge Glass Company attempted to impress the test design provided by the mint onto nearly molten glass that was then allowed to cool. After many attempts, the results were disappointing. The process was not only littered with failures, but also offered little hope for efficient and uniform mass production.
Up to now, the only extant 1942 glass cent pattern was broken in half. (You can imagine that these small, ill-fated experimental coins made from glass were far from sturdy.) The newly discovered intact pattern, held in a private collection, is reported to have a transparent yellow-amber appearance. Its details are much softer than normal coins and the surface exhibits minute cracks and irregular glass flow patterns. The design used is the obverse from Colombia's two-centavo coin while a simple wreath surrounds the text "UNITED STATES MINT" on the reverse.
Because it is truly a unique specimen (one of a kind), there's no telling how much this glass cent pattern would sell for at auction. It's unclear whether it will ever be available for sale, however.
The opinions and forecasts herein are provided solely for informational purposes, and should not be used or construed as an offer, solicitation, or recommendation to buy or sell any product.