Is it possible that the coftgari is new altogether? Koftgari technique is still practiced in Middle East and India, and there are many masters who create good quality work. The geometrical coftgari on this Yataghan is relatively simple, and even unusually simple in comparison with known old types. The condition of silver strikes me as being a bit too newish in comparison with condition of the blade.
Sandeep Singh, who is Forum member, and one of the best coftgari masters in my opinion, perhaps can comment on this (and I think he can do a better work by the way