I am just curious if anyone knows why sand is different colors. For example, in Hawaii there is the Punaluu Beach, which is pitch black. There are also pure white sand beaches and even a pink beach in the Bahamas.

What a great question! I really don't know why sand is different colors. I haven't ever seen black sand before. That seems odd to me. It must have something to do with something in the water. Then again why are there so many different types of grass? Climate right.

I think it has to do with the different minerals and rocks in various regions. Not all sand is made up of the same particles, so it makes sense that there are color variations.

All sand is pulverized rock, really, so what you see is the result of what kind of rock. The black sand comes mainly from volcanic rock. Where I live, the beach consists of reddish sand because there is a lot of iron and clay in it.

From what I remember of my high school geology, that beautiful white sand which you typically see on tropical islands originates from limestone, which is similar to chalk. They're both very soft types of rock ('sedimentary' as I recall) so make for soft and powdery sand...the kind that feels nice between your toes!