Hi Jim,
Robert and I visited Florence, during this period, and I cannot remember seeing any walls of stacked deads there.
Another point against Florence, is the relative cleaness of the overalls.
When you come out of a West Cumberland iron mine, everything you touch is red!
These miners were not known as the red men for nothing!
Obviously this is in black and white, but I would have thought that marks on the overalls, would be obvious.
I wonder if it was in one on the Alston Moor anthracite mines?