and inventor Gary Greenberg started taking photos of sand grains with his own light microscope more than a decade ago. Each sand grain is about a tenth of a millimeter in size — which is the ...

Millions of sand grains. What you probably can't imagine: at the same time, billions upon billions of bacteria are also trickling through your fingers. Between 10,000 and 100,000 microorganisms ...

Scanning electron microscopy reveals the shape and texture of a quartz sand grain from the Mississippi River. The pictured sand grain is about 200 micrometers in length. Credit: Michael Hasson, ...