Looks like you're doing a carnie site that has gone undetected for the most part. Bet you left a few targets in the ground too! If you're discing out the iron, you'll miss those cotter pins that hold the rides together, they often mask lots of coins. Another carnie site trouble maker are the cheapo curtain hooks used at some of the game tents. They don't sound off on most detectors but effectively mask large areas of ground unless you have a good all-metal machine and are digging all the signals. Looks like you've got lots of digging in the near future. If you're also finding small brass light bulb bases with or w/o glass then yep, you're on target!