Never seen the movie , but damn that is an all star cast . <| sep |> Trump loves to fuck with people , it ' s so god damn hilarious <| sep |> The greatest weakness of glass is its inability to bend . Metal bends under pressure because it is polycrystalline and grains can slide past eachother . True glass has no crystal grains at all and is an amorphous solid . Glass such as fused quartz is one big crystal grain . If you try to make a polycrystalline glass then you find that this is very easy and can be done by accident , but the material is usually no longer transparent because light trying to pass through it reflects off of millions of grain boundaries this is only part of why metals are not transparent . However , if you make the crystal grains small enough that they do not scatter light much then you can have transparent polycrystalline ceramics . These are still a little brittle and often slightly less clear than you would like , but would satisfy your desire for a bulletproof shotglass . The transparent aluminum which has been in the news and on armored vehicles is aluminum oxynitride . Borosilicate glass aka Pyrex is a true glass which is still pretty tough and much cheaper . Normal glass explodes when dunked in boiling water because part of it expands with heat and part of it is still cool , creating huge internal stress . Borosilicate has an extremely low coefficient of thermal expansion and is nearly immune to that , but can still shatter if you drop it on the floor . If you want an affordable transparent coffee cup then this would be the material of choice . I knew some people in college who were trying to make ceramics which would shift crystal allotrope under pressure as a way of dissipating impact energy without bending , but AFAIK this was a miserable failure .