There's a rock at the main intersection of White Rock, New Mexico that's often repainted, sometimes two or three times a day. My pal Mouser and a couple friends of his took a core sample of the rock to determine the paint thickness...turns out there was five and a half inches of paint on that rock. Here's a composite photomicrograph of the paint layers.
Best viewed large.
My pal Mouser has started a sand collection and is using a macro lens to take photos of each sample. This sample was collected in Hawaii.
The green grains are olivine, the black are basalt, and the white are possibly bits of shell. Green sand is reasonably rare; the southern tip of the big island of Hawai'i is the most common place to get it.
Don't miss the star sand. And in this shot, you can see fossilized shark teeth.
If you want to add to Mouser's collection, you can send him a small sand sample (about the size of a film canister) here:
128 Rover Blvd.
Los Alamos, NM 87544
My pal Mouser is in Kazakhstan and took a bunch of photos of kids doing parkour on the beach. This shot is my favorite.
Will parkour eventually join soccer as one of the world's most egalitarian sports? You don't even need a homemade ball to play, just stuff to jump over, through, and off. The whole world's a course.