There's a bit of a difference between flood gold and float gold WC. Flood gold is the result of erosion of benches and ancient river deposits into a river system like one would find in California's Sierra Nevadas. Boulders are moved allowing for a redistribution of existing free gold and more coarse gold is added to the riverbed...in some instances, a lot of placer gold is added! Float gold is very fine gold particles that are more easily picked up in a flood or high water event and deposited along the banks and flood plain. WRT your French Broad River, I could really tell you anything special as I have not prospected much in the eastern US. Accessibility is different as in the Eastern US it is all privately owned land, and western US is predominately BLM, Forest Service, or Military. You can tell that spring is in the air, and I am waiting for the snowpack to start melting (smile). Be well, and stay warm. S~P