kcm
Gold Member
That would probably be too slow if incoming water is a concern.
Do an internet search on Sand Scoops. They have a handle and usally a step to drive it down, but it is just a cylinder with holes in the bottom. Large enough for the sand to filter through and small enough for rings, coins, ect to stay. If you put a weight on the front of the barrel to make sure it Digs into the mud, then you can trench deeper and deeper in the same trough. Use water from the river to clean any left over mud to check the screen. You could lift it up onto like 2X4's and then pour the water in and stir the mud, when the mud is gone, do it once more to see if and coins are there on the bottom.