Diatoms are single-cell organisms that make a silica cell wall. It's covered in dots and lines. "Diatomaceous Earth" consists of countless species and numbers of Diatoms. Diatomaceous Earth/Diatoms is a good carrier for Bio.
Identification of “Diatoms” is easy. Look for clear, non-fluorescent geometric shapes with some “sculpturing”, i.e., dots and lines.
They usually are not autofluorescent.
