Hi Julian,
I'm afraid I can't take credit for blazing the trail, I got the blades from a good friend of mine who's a bladesmith who uses them quite a bit. They do make excellent knives, though. They're not stainless, but they are quite rust-resistant. I'm not sure how old they are, but at least a few years, maybe four or five.
As for forging porperties, it's very strange. It's close to an air-hardening steel, and is difficult to file when cold. Though I actually forged these blades, my friend primarily stock removes when using them. He only forges scrolls of large bends, and I'd have to say that that is probably the best course of action for this material.
I'd like to get the exact properties of this steel, I'm probably going to give a piece to a friend who works in the Chemistry dept. at the university to analyze.
You can see Dan's work here: www.blackriverblades.com. He uses the skate blades mainly for the bodice daggers.
Cheers,
Nick