A single magnified diatom
Diatomaceous earth, also known as DE, is a sedimentary rock found in large deposits worldwide and mined primarily in the United States, Mexico, Chile, Peru, France, Spain, Denmark, and China. Northern Nevada has several large, high-purity deposits mined by EP Minerals, a U.S. Silica company. The DE is developed into hundreds of products used around the globe by the world's largest companies.
The diatoms that are forming today - the single-celled plants that make up the diatomaceous earth - are truly the lungs of the earth, in that they produce about three quarters of the world’s new oxygen supply. See, DE is a really big deal!