Steven K. writes: recently i found a penny that i don’t have an explanation for. It is a “shell”, the reverse is clearly stamped (lincoln memorial) complete with rims but the obverse face and interior is completely missing. It is almost like the entire interior has been drilled out, however there is no evidence of drill or cut marks. The marks inside the “shell” are all oriented in one direction, not circular. i am at a loss to explain this item, any help that you may be able to offer would be very much appreciated! Thanks!
There are lots of examples of cents and other coins being hollowed out at a machine shop for various purposes (see magic coins). Though the inside of the “shell” usually has circular marks, I’ve seen pieces that were etched on the inside to accommodate a filling such as a jewelry mount. Coins are used in more ways than for money.
The most interesting use of “shells” that I’ve seen was the economical use of a gold Liberty Quarter Eagle hollowed out to make cuff links. One would normally see cuff links made with two coins but these were no doubt made from the same coin. On close inspection, you could see that the coin was cut in two, the gold scraped out and a torpedo inserted into the back of the empty space. I guess if you disassembled these cuff links you would probably see the marks that you described in your note.