Mounting the filesystem, on my debian box, resulted in the dialog informing me it was mounted read-only...
The card lock was off...
I googled it...
fdisk said it was fat16...
ls said it was in the floppy group; I'm already in the floppy group...
Root can't mount it, either, with write permissions...
ffs...
As a daft experiment I tried to mount it, as a normal user, with the card lock on: success! Oh...
Happy new year everyone!