Bravozero
Drroooiiiiddddd
Normal glass has a hardness of 6-7 on Mohs scale, whereas steel (an Fe-containing alloy) in jewelry typically has a hardness of 4-8 depending on the composition (low for C-steel, high for W-steel). Brass keys (copper and zinc) have a hardness of 2-3.
So, your "girlfriend experience" may not be that diagnostic.
Haha, thanks for the technicals. I wasn't going to pull my Benchmade knife out and carve away, that's not a fair test. Just as long as the damn screen doesn't scratch up easily that's all I'm concerned about.