A dagger?
 

Anybody know what this thing is? Unfortunately I didn't win the auction for it but I'm still curious what it is.

The tang is almost as long as the blade.
How unusual!
The stub of a sword blade repurposed?

It also looks like at least half the ricasso wouldn't fit into the scabbard. Maybe the scabbard was re-purposed from a different dagger?

The point of the blade seems untouched, converging fullers and all. Could the ricasso, being originally a long one, have had part of its section narrowed, thus elongating the tang ? Such a riddle !
It is true the nice scabbard doesn't properly match.

I have in my collection a dagger whose dimensions are practically the same as with the dagger above. Unfortunately the scabbard is missing but the ricasso is similarly made although with only one fuller on each side of the blade.
corrado26

Can i humbly question that, corrado ?
The blade in your dagger is over 70% of the whole thing, whereas the blade in the item posted is less than 64%, which makes a decisive difference.
You will also pardon me but, i don't see such a similarity between both examples. But i might be blind, of course. :o

The seller gave the following dimensions:

20.6 Long without tang
Ricasso width : 1,9cms
Ricasso length : 3.5 cms
Thickness : 4mm
Length of the tang 12.2 cms