system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why does a pile of broken glass look blue?
gpt
Window glass is actually greenish. You don't notice when looking through a thin pane, but if you look through it edgewise or through a thick piece, you'll see it. When you look at a pile of glass, the light passes through many pieces and the color is more apparent.