Help, what style of knife is this and what country do you think its from? the blade is 3 1/2" closed its 4 1/4" . the grips are some kind of pearly plastic, it has a brownish film or patina on most of the blade, liners are steel. It has no markings on it anywhere. thanks for the help.
here is the notch for the locking blade, you can see it has either worn or someone smoothed it up so it can be closed without the missing ring or lever.