You Can't Sheathe It, Either

“Excuse me?  Could you tell me why this sword is so highly priced?”

“Ah, that’s because this is a mollyblade.  The edge is single-layer graphene, less than a nanometer thick.  It’ll slice cleanly through anything but muon metals, gluon string or neutronium – or antimatter, of course – and we can make-to-order one for you that’ll slice muon metals, too.”  The shopkeeper carefully slashed the blade through the air.  “See the glow around the tip, where the blade moves fastest?  Dissociated air molecules recombining.  It’s that sharp.”

“And that costs a million esteyn?”

“Well, not strictly speaking.  The problem with the mollyblade is that a blade that sharp is also fragile.  It damn near blunts itself on air molecules, too, which is a problem a lot of the lab applications don’t have.  So what you pay most of that million for is the on-the-fly resharpening system that keeps it that way while you’re hacking and slashing with it.”

“Which is…?”

“Proprietary.  Very proprietary.”

– overheard in an Eye-in-the-Flame retail outlet