Salaams all... Its quite difficult to be definite from the pictures but I still think Rhino. I think I can see what could be the tell tale spaghetti endings otherwise not seen in any of the photos. ... at #1 on the second photo where the light catches the hilt at the end of the tee shape.
There are several colours of Rhino horn moving through the spectrum from dark almost black through to light brown to chrystaline yellow and white with varying degrees of transparency...In the Yemen each grade and colour has a different name...and rarity. Good luck with your quest..
Regards,
Ibrahiim al Balooshi.