Amosite, Condenser Central Stop Dispersion Staining
Transmitted Phase Contrast with one linear Polarizing Filter Oriented Perpendicular to the Fiber Length

The D-line refractive index along the length of this sample of amosite asbestos is about 1.680. It matches the refractive index of the Cargille High Dispersion 1.680 liquid at a wavelength of about 590 nanometers. At this wavelength the Cargille liquid has a refractive index of about 1.680, as does the amosite. This Type of Dispersion Staining produces two colors, one for the body and one for the halo outside the particle. The body color here is a sky blue. The halo color is an orange/red. The two colors provide a comparison for assigning the wavelength at which the liquid and the particle match. Phase contrast dispersion staining has a very shallow depth of field and retains the high resolution of the particle image. This type of dispersion staining works best with small particles or fibers. It is ideal for asbestos fiber identification.