is glass sharper or is a blade sharper?

[babypeppie]

is glass sharper or is a blade sharper?

[elegantly]

Well im pretty sure that surgeons use metal blades and not blades of glass!

[Clanad]

Actually, manufactured glass, naturally occuring obsidian and even flint all are very rigid and brittle. Thus, when they are fractured, the breaks occur along a path that produces an edge similar, at the microscopic level, to a hollow ground blade. Scalpels and other finely ground metal blades cannot achieve this sharp of an edge since they are flexible. They are, however, more durable.

Some of the sharpest blades are made from ceramics today...

[1ARMEDBANDIT]

I used to use bits of broken glass to take the old varnish and laquer off old snooker and pool cues, also used it to smooth them out. It was sharper than blades, more accurate, left a better and smoother finish and was a lot cheaper. When the glass eventually lost it`s edge I would snap off a new bit.
I was repairing and cleaning old cues this way for 20 years and never once cut my hands either.