If that is wood one can do a Carbon 14 test on the wood, assuming that the wood is original to the forging of the blade, otherwise it could be a later addition to an older piece of metal. Such information would not be conclusive but would be suggestive of a time period. The blade reminds me of early Imperial Rome. If so, it is a very valuable find. While Ancient bronze arrow heads, dagger blades and spear points are fairly common, ones of iron are not. Live near a University with a good Ancient History department and access to chemical analysis?