Atlas of Foreign Materials
A major group of algae, they are a common type of phytoplankton. Most are unicellular. They have a silica cell wall and are bilaterally symmetrical, but have many different forms. They are small enough that they can be inhaled and thus tend to be found in the nasal cavity and sinus area. Individuals working with diatomaceous earth would seem to be the most likely to show this material.
You are welcome to download these images. Right-click (PC users) or Ctrl+click (Mac users) and select the Save feature.
Diatom aulacoseira medium power
Diatom aulacoseira high power
Diatom aulacoseira or melosira oil mag
Diatom aulacoseira or melosira 2 oil mag
Diatom cyclotella comta high power
Diatom cyclotella comta high power 2
Diatom cyclotella comta oil mag
Diatoms cyclotella comta and aulacoseira medium power
Diatoms cyclotella comta and aulacoseira high power
Images courtesy of Texas A&M University Baylor College of Dentistry