I had a weird thought today while driving around down town, one that I'm not even sure there is an answer too? But I was thinking, why is metal non transparent while glass is? And not just metal and glass, those are just examples. I guess it would be better to say, why are transparent things transparent and non transparent things non transparent? But that might be too vague of a question since the molecular and chemical structure of everything is different. But I'm thinking it has something to do with the molecular structure of things, but I guess you can say that for just about anything.
So does anyone know the answer? Its kind of a strange question, but I thought it was pretty interesting/fun to think about. I mean, if we could create transparent metal, how freaking awesome would that be?! It might not be possible though, but hey, the world ain't flat now is it?