I’m having a hard time dating this Chinese ox-tail broad sword (niuweidao). Any advice or suggestions would be appreciated.

Steel blade: 29 ½ inches long from guard to point; 0.21-inch thick blade at root, tapering to 0.12-inch at mid-point. Back-curving blade is 1-inch wide at hilt, then swells to 1 ¾ inch wide before coming to a sharp point. Blade is sharpened starting 6-inches from the hilt. Two pairs of blood-grooves (fullers) on each side, with brass inlaid circle between each of the four segments. No visible signature or symbols stamped on the tapered tang. Dragon is stamped on both sides of blade, approximately 5-inches long; open mouth.

The oval-shaped cup guard is steel. Wooden split-grip covers the tang; wrapped with natural-color braided rope. Brass band at the guard-end of handle. Brass pommel has small hole aligned to the tang.

The spiral wire-wrapped scabbard is wooden with ornate black lacquer or leather finish. The scabbard’s fittings are brass. The harness attach bracket is steel.
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