Strange blade on Chinese decorative sword
 

I probably bought this off E-bay 15 years ago from a seller in China. The seller made the usual claims about it being an antique but I'm sure it's relatively brand new and intended for decoration. I put it in a closet and didn't give it another thought.

I took it out recently and noticed the blade had an odd pattern on it. There's a wavy line on each side of the blade, almost like a hamon. You can feel it if fingernail over the wavy line so I think it's more than just an etching. It almost looks like the blade was made from three pieces of metal welded together. Or maybe the blade's laminated?

Sanmei (or etched to look like it).

No opinion on age or authenticity of the piece from those photos.

All the brass parts are cast rather poorly and look like they've been artificially aged. The casting lines have been ground down and then hammered over so they're nearly invisible, so somebody put some effort into making it look authentic. I'm sure it's not "real", but the blade intrigued me.

http://www.fightingarts.com/reading/article.php?id=128

I found this page describing the different kinds of Chinese metal working. I think this blade looks more like the twist core example than the sanmei one. Maybe it's some kind of simulated or "fake" twist core. I can't imagine it's the real deal.

Sometimes these have sanmei blades. But the ones with a "jumps out" pattern like this are usually just etched fake sanmei.

In my experience, Chinese twistcore swords are sanmei with twistcore cladding on the sides, rather than a twistcore body with a welded edge. This example does look like welded-edge construction more than sanmei, but I think it's just bad imitation sanmei rather than imitation welded-edge (or real welded-edge).