The hole is said to be lucky, the characters (identified by my good and knowledgeable friends on the WELL as spelling out the mint date (1988) and the words "go-en" which mean "5 yen" and also sound like the word "fate," according to this guide. The sheaf of rice curves over rippling water and around the hole, itself ringed by a gear. It's brass, and relentlessly pretty. I found it in a parking lot. People are said to keep this coin for luck, or offer it at temples for prayer. I'm not sure which route I'll take, being non-Buddhist and non-Shinto, and only vaguely superstitious. Meanwhile, my son has spirited it away to his "box of treasures."