system
Given the following post, respond as if you're commenting on Reddit:
human
Eli5: why can't metal be clear?
gpt
Typically, the same properties that make metals conductive (the way they move electrons) makes them opaque. Color and transparency relate to how photons (light) interacts with a material. So something is transparent when photons can pass through roughly without distortion. In metals, however, there's a cloud of very mobile electrons, and these usually absorb and reflect incoming photons at random. This is why most metals have a silver/gray shiny appearance. They reflect light in a number of random directions, and they reflect all wavelengths roughly equally.

That being said, there are materials like aluminum oxynitride that are transparent. Google it for cool pics.