A dagger blade ... and questions, please
 

Now, what would this blade be for ?
Certainly for a dagger but ... what type ... and where from ?
The grip, how would it be ? Could anyone here show me an example ?
The tang end has a screw thread. Would it have a pommel ... of the (approx.) spherical type ?

Could any of you guys answer some of these questions ?

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Could be from a Russian Naval Dirk....

Blade from a trench knife maybe?

I think its safe to guess that it is indeed a dirk, judging from where the pommel would have screwed onto the tang. The trefoil blades were seen on some naval pieces, as David pointed out. Likewise, some generic boot knives had them. Hmm, without markings, its hard to pin this one down for sure. :shrug:

Thank you for your kind assistance, guys.
Yes, the cross section like i (think i) see in the Russian dirks shown by David tend to be more the thing. I have then tried to explore data info in the web but, the examples that popup are more towards the (early) 20th century, whereas i think my piece is as early as 19th century; not so fancy, shining and all.
Also a (an)typical detail is the recasso cross section; besides this being a three faced blade, with one purely flat and he other two in a concave attitude, the 'upper' edge starts after a curve, leaving a space between it and the whatever guard mounted to it.
Would you guys say this is as common as to not to point to something specific ?

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Rather handy for thumb control.

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