I've seen that in the Patent database.
Check here Gold Pan Patents
Found this in a buddies garage. Is there anyone who has seen one before?
That is a nice idea. I might take one of my pans and do that.
How about making a little larger, and putting a small motor on it with an off balance to make a small shaker table and sluice combo.
Use it just for material classified down to 1/8th inch say.
Stuff we take home.