Thank you for submitting your item for appraisal. This appears to be a large Indo Persian dagger, with curved double edged Damascus steel blade with Islamic cartouche at center, sheath and mughal India style hilt with knuckle-bow entirely silver koftgari decorated, possibly late 19th century. Similarly decorated tulwars / talwars, shamshir or pulwar can be found all over Persian and the areas formerly controlled by the Ottoman empire. The estimate is base on current auction results. "Asking prices" in the trade can be much higher and vary.