Does silicon dioxide have a high melting point? Why or why not?

$S i {O}_{2}$ is a homologue of $C {O}_{2}$, a molecular, room temperature gas. Silicon dioxide is non-molecular, and forms an infinite array of $S i - O$ bonds. On the other hand, the shorter $C - O$ bonds allows $\pi$ bonding between the 2 atoms and a discrete molecular structure.