Would you eat this? It might look like a crunchy new breakfast cereal, but it’s a close-up of diatomaceous earth, the fossilized microscopic skeletons of diatoms. Diatoms are unicellular algae, one of the two major classes of the phytoplankton that constitute the bottom of the food chain in oceans and freshwater. Diatomaceous earth is a soft, siliceous sedimentary rock containing… READ MORE "Diatomaceous Earth? No Thank You!"