Hints of a chain link.
A used striker will show abrasion/ scratches on an edge. An edge that will be flat. Room to fit fingers and not hit them with sharp flint is common.
Hardness matters for a quality spark as minute fragments of molten steel are carried off the surface when hard steel creates resistance. 6 1/ 2 hardness level is good.
Not suggesting any destructive testing ,but the edge struck with flint will not be soft.
Looks like there may have been something attached to it going by the first picture showing the flat spot in the bottom middle. My guess is a sardine can opener!
Looks like there may have been something attached to it going by the first picture showing the flat spot in the bottom middle. My guess is a sardine can opener!