Every so often I clean a local CU out of $50 Bags of cents and sort them. The bank is nice and the tellers are trilled to sell them to me. So its a cool connection.
On the bags now they stamp their address in a 'From' box and in the 'To' Box they stamp the address of my area's federal reserve bank. So it is safe to say they cut to the quick and give them directly to the FED. This is nice information to have.
So if I was to do a zinc dump these pure bags would go to the FED and would likey mix with other bags, decreasing copper percentage, but not likely to create dud boxes. Does this seem correct?
I think there is more to it. I get my pennies from a local credit union that get's Brinks boxes. I marked the about 1000 zinc pennies with a Green T on the obverse. I dumped my zincs at another credit union that has a coin counting machine (bags them). That credit union also uses Brinks. I had several of my marked pennies in my Brinks box pickup the following week. There is no way that these pennies left Indianapolis for the Fed, and then came back to Indy within a few days.