Artifacts, Not From Blood
Glass fragment, from the edge of a slide, not from the patient.
Note that the fragment diffracts light, is crystalline in structure. And is it not affecting, nor harming the surrounding cells.
Cotton strand, no stain. Notice the long fibers, and also the frayed end, and the frayed break on the left. These tend to be blue or light blue with no stain.
Parasite worms would display varying and roundish width, with tapering on the ends. The color would also show blue edges.
A bacteria string would be greenish in color, without stain.
Carbon crystal, from air exposure, not from the blood of the patient. It is not touching blood, nor is it affecting blood, therefore came from air, and carbon is usually due to automobile exhaust or fires.
Talcum (petrified animal) shed from powdered gloves. Always use nonpowdered gloves when viewing blood.