Here's why:

* Composition: Sand is primarily made up of silicon dioxide (SiO2), which is a compound of silicon and oxygen. Silicon and oxygen are both non-metals.

* Properties: Metals generally have properties like being shiny, malleable (can be hammered into shapes), ductile (can be drawn into wires), and good conductors of heat and electricity. Sand lacks these properties. It's brittle, not shiny, and a poor conductor.

So, while sand might contain small amounts of metallic minerals, its main component is a non-metallic compound.