system
Given the following post, respond as if you're commenting on Reddit:
human
Possibly a stupid question... why do ice cubes generally look clear, but when you shave the ice, the shavings look white?
gpt
The same reason polished and cut diamonds are clear, while rough diamonds are generally opaque. When ice is shaved, it gets a rough outer surface which refracts light in many different directions. Ice cubes are very smooth and so light passes through them and refracts more evenly.