I just came across this article and thought it was very interesting. I hope it's okay to post the link. I also realize it's old. I had never given much thought to what a grain of sand looks like. Some of it looks like the specimens I've seen on here, only microscopic. Makes me want to check out my local beach and find a high powered microscope.
http://www.boredpanda.com/magnified-sand-grains-microscope-photography-dr-gary-greenberg/?media_id=sand-grains-under-microscope-gary-greenberg-4