Hello BV,
Thank you !
Yes the blade is still sharp ( I wounded my thumb testing it !
)
Maybe ceremonial dagger made in the 19th century in France ( violet le duc )
I thought about what you said, the link between lys and dragon...
It can be a François 1er dagger, his symbol in heraldics was the mythical salamandar ( who didn't burn into the fire !) look like the quillons ends ??!!
and the lys is common too in french royal families