Can you make glass out of cubic zirconia, like you can with sapphire?
It would no longerbe cubic zirconia if you did, the cubic part refers to the crystal structure of the material. You can make a glass out of many materials (including pure metals) if you can cool it sufficiently enough. Have a look at the glass transition.
If Wikipedia is to be believed, sapphire glass is not a glass, but a crystal. The crystalline structure of corundum is preserved. The (German) entry 'Saphir' is more categorical in that point: Die Bezeichnung ist irreführend, da Saphirglas kein Glas ist. Saphirglas besitzt eine kristalline und keine glasartige (amorphe) Struktur.
Good point, sapphire is a crystalling transparent oxide with a large band gap (~9 eV), rather than a true glass.
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