Which is better, 3d curved glass or sapphire?

Does the subject want to ask "which is better, 3d curved glass or sapphire glass"? Sapphire glass is nice.

1, sapphire glass is extremely hard, which can effectively prevent mobile phones and watches from being damaged, while 3d curved glass is fragile and easy to crack.

2. Sapphire glass is a kind of artificial glass, which is made by melting high-purity alumina, while 3d curved glass is a translucent glass material.