How to date (powder) horn?

[BBJW]

Originally Posted by fernando

I assume this rustic powder horn is Portuguese, due to the circumstances, but can not be sure .
I wonder how old it could be. Its body has scales, a condition i am not familiar with, and it has worm holes, something i have already seen in other horn articles .
Does any of these sympthoms represent an age grade, or do they also happen in "modern" horn ?
The wooden plug and butt cap also show age ... could be the originals, so as the ring.
The zillion pictures are an atempt to show its texture in the various positions.
Coments will be wellcome.
Fernando

If this is Portuguese my question would be when did muzzle loaders stop being in common use? At any rate they are hard to date.
Cheers
BBJW