Thank you Tom and David for the further posts
personally I am convinced that this is a re-mounted spear head and almost certainly of SEA origins, whether this was hilted (or even re-hilted) in Europe is another story. I have been unable to find a similar dagger described as European ....all the examples I have found (with very similar features to my own) have been attributed to SEA (some with pamor... most without)
The 'balance' and solid construction seems to suggest that this dagger was made with care for a purely functional use....to stab. I have considered this to be a 'hunting dirk' but it really does not fit the 'profile'.
I suppose, with weapons that are not readily easy to ID, you have to weigh up the comments of others, your own knowledge and the 'feel' of the weapon in question.....until proved otherwise.