[hyeparis]

2 Mr. X. Thank you for asking the question.
It is actually a traditional Dagestani daggar made in Kubachi, a village in the Northern Caucasian republic of Dagestan, which does nothing but daggers and other metal works, such as sabres, but also bows, etc. in line with their centuries-old tradition.
This one is ceremonial and has a lot of engravings, so it is not mean for use, only for wearing with the traditional Dagestani folk attire. Russian Tsars when dressed in Cossack uniforms, which look very similar to a folk attire of a Dagestani (or most of other NC peoples for that matter), would wear such daggars too.
I proud myself in pioneering use of these daggars underwater and get a lot of respect from other Caucasian spearos cause my knife is usually bigger than theirs.