A rare glass penny is set to go on the auction block, but if you're thinking of bidding, it will cost you. The AP reports that the US Mint, faced with a copper shortage at the beginning of World War II, approved experiments to make pennies from other metals, plastic, and rubber. A Tennessee company made some from glass and failed so spectacularly that only one known unbroken penny remains. (Another broken piece is also known to exist.) The precious penny is set to be auctioned on Thursday by Fort Lauderdale-based Heritage Auctions, which is hoping it will bring in more than $30,000. Coin expert Roger Burdette bought the penny last summer for several thousand dollars. "I knew pretty well what it was from the illustrations, but I couldn't be sure without examining it and that wasn't a possibility without buying it," Burdette says. "These things have been so poorly documented."
After the US entered the war in late 1941, the military needed most of the nation's copper to make ammunition and equipment. Looking for a replacement, the Mint handed out dies to companies willing to make experimental pennies. The now-defunct Blue Ridge Glass Co., of Kingsport, Tenn., made an unknown number of pennies from a hardened, yellow-amber glass resembling a cough drop. Other experimental coins made from low-grade steel covered with zinc looked too much like a dime. By 1944, the Mint began making copper-based pennies again, using spent military shell casings. As for the glass pennies, Burdette says they didn't have the precise images needed and couldn't be made a uniform size and weight; they developed sharp edges that cut fingers. The company got rid of most of the stock, but Burdette was lucky to find the sole survivor. (Read more penny stories.)