Of course, the pieces above have been meticulously polished and cleaned, but I'm honestly baffled at the beauty of them. What you're looking at exactly is mostly organic matter–fragments of shells and coral–magnified at 250 times under a microscope. The rest is volcanic rock, crystal, and certain minerals.
I know for sure I'll never look at sand the same way again.
A ton of more pictures can be found at sandgrains.com.