A cannon or a mortar ... old or very old

[fernando]

What do i do with this?
Found in the basement of a local XIII century fortified tower.
It isn't necessarily part of the tower belongings, as it doesn't have to be such an early piece.
It was kept in a little niche on the wall, although its excavated condition shows that it must have been on the ground for several years.
Certainly rought iron ... not cast.
The height measures 14 cms; the bore about 55 mm. The "touch hole" is rather large, with its approx. 15 mm.
I gave it a couple (thin) wire brushings but the rust didn't move much.
Should i be more radical, like search for a sand blasting?
Any opinions ... Miguel ... guys ?

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