There are many things with different textures that appear white – salt, beer foam, paper, shaving cream, snow, talcum powder, white paint .., etc. The most common answer is all of the frequencies must be reflected in order for us to perceive white –, which I already know this. There must be more underlining details why such a huge variety of things are white. Furthermore, if you wet paper, snow or talcum powder, they appear off-white or gray. Why is this?