Hi Mauro, thanks for posting the translations.
I've read a bit of Morel before, it is of course an important work but entirely Tuareg centric while the takouba form is not.

The Tuareg beliefs regarding the need for talismanic brass and copper elements were obviously not shared by all the other takouba using peoples although many of the designs found on leather were.
Yes, the vast majority of blades used by the Tuareg were imported, mainly from Hausa cities like Kano.
The note on the idea behind the pommel for the Tuareg is interesting. I wonder which pommel form it refers to though? The stacks? Or the earlier flatter pommels? Or the oval pommels? I think you have seen them before but the earliest Tuareg swords I am aware of, where we have true dates for the hilts, are these
http://blade.japet.com/takouba.htm (scroll down the page).