Pencil Lead Dust
This is one of a set of three images that shows the appearance of pencil lead with different types of illumination. Here the depolarization at the edge of conductive particles is illustrated. Graphite is sufficiently conductive to show this effect. This is from an environmental tapelift collected in a school classroom.
Transmitted Crossed Circular Polarized Light
with reflected light.
Definition/Function:
Pencil debris includes the carbon fragments from the "lead" of the pencil, wood sawdust, and paint from the surface of the pencil. The carbon fragments are actually a blend of clay and graphite.Significance in the Environment:
Characteristic Features:
Graphite is relatively reflective and so the particles from the pencil lead are speckled when viewedwith reflected light.
