I did a two hour hunt, and I came up with 172 yen, or about $2. I also found a token with the US seal on both sides, which was pretty cool. Enjoy the pics and HH.
Great question! I have an Ace 250. 500 yen reads up between penny and pulltab, 100 yen reads up as nickel (Not a surprise because the coin is almost the same composition as a US nickel) 50 yen reads up as a nickel again, exactly the same alloy as the 100 yen. 10 yen (By far the most common of all of the coins that I find) rings up as a dime. 5 yen reads up as a penny, and 1 yen as a pulltab/dime. 1 yen coins are 100% aluminium. But keep in mind that these readings are mainly bench-test readings. Due to the high mineralization in the ground, the readings can be way off. Yesterday, a 10 yen was reading up as iron and dime.