Hello,
Thank you all for your comments !
50's just begins to be old for humans, for a jambiya not sure

hopefully it's not too recent.
Interesting the ''amberoid'' I didn't know it
I wonder why they used to do this kind of hilt materials instead wood or marble-stone handle and why they mixed it with real silver filgree-mounts.
- Was it to sell it high priced as a rare rhino hilted piece to the few
( I think !?! ) present strangers ( for British ? with the Aden Protectorate... )
- Or for local people who liked the similarity with horn hilt but hadn't enough
money to buy one ? ( like skaļ-imitation leather instead of real one )