And between steak knives. The steak knives I have in my kitchen block would do it (although probably too narrow), a cheaper, thinner steak knife like you could steal from Sizzler would bend when it struck bone.
Those who think Arias used a straight razor (that's the kind with the long hinged handle and finger tab, the kind you unscrew and put double edged blades in is a safety razor) have apparently never used one. The way one holds a straight razor means not a lot of pressure can be applied. It's designed that way so someone shaving or doing the shaving has less chance of cutting into flesh. Once bloody it would be almost impossible to hold.
Also, are we to think she switched from a stabbing knife to the straight razor during the attack? Sure.
Thing is, practically any knife with a six inch blade and a rigid back, from a kitchen knife to a KA-BAR to some cheap evil-looking novelty knife would be more than up to the task of doing the stabbing and throat cutting. That Arias had an injury to her smaller finger on her dominant hand that is typical of her hand slipping down onto the blade suggests she used a knife with little or no hand guard, which would mean more of a kitchen knife than a tactical knife.
Her parents owned restaurants. You think the family has enough kitchen knives kicking around that one or two wouldn't be missed?
