Diatomite is one of the important type of rocks. If we have to define Diatomite in general, Diatomite is a fine-grained sedimentary rock which is formed from consolidated diatomaceous earth. Diatomite comes under Sedimentary Rocks. All Sedimentary Rocks have similar properties and formation process. Along with Diatomite Definition, know more about the History of Diatomite, Etymology of Diatomite in next sections.