It is a member of the Rosewood family. I would say that redwood and teak are out. But remember that "rosewood" is not a single wood but a whole family. We can eliminate the lighter members right off the bat (tulip, flamewood, ect).Although Madagascar rosewood is the same tone. it tends to be more even in color. I am going out on a limb and say cocobolo. For several reasons. First the grain structure matches. Second look at the color variations. In the middle are two bands of tannish pink. Then at the bottom are at least three bands of near black. Third, cocobolo is one of the most common woods used in knife handles.
Aprox. age would help alot, but that not known I would say 100% rosewood family 75% cocobolo.