It's also highly brittle, with a fracture toughness of 2 MPa.m1/2 -- which makes it only marginally tougher than borosilicate glass, and broadly equivalent to many brittle ceramics such as silicon carbide.

6061 aluminum has a fracture toughness of roughly 29 MPa.m1/2.

So "transparent aluminum" exhibits fracture behavior that is much more glass-like than aluminum-like.