Here is a old way of storing your cartridges . No work involved. just takes years to get them this way. Box is till in good shape. Any thoughts on cleaning the cartridges .???.
Vinegar(warm) and bronze brush.
Corrosion is due to Chlorine-bleached paper-pulp, and moisture/humidity/condensation.
What was the Packet ? DOMINION or other brand?
I soak them in vinegar and it usually clears everything. I put it in a plastic test tube and swirl it intermittently to help the process. With that much contamination you will need fresh vinegar for each of them. Sometimes I leave it soaking overnight, then everything comes off. And you will be able to read the headstamp after vinegar. Nice box.
Ironically, I note the box reads “SUPER CLEAN”.
Sounds to that that is false advertising. LoL
Thats a Dominion Box