Assemblage Analysis and the Microscopical Identification of Particle Sources: Wildfire a Case Study

Assemblage analysis is the use of multiple particle types created by a source to identify and quantify the presence of particles from that source. The approach presented here is limited to the case of debris from wildfires though it is applicable to tracking any particle source. The first step in applying this method is to characterize the source and to identify and characterize the particles created. The particles carry their identity in their optical properties but much more than their identity is present. Artifacts including size, texture, color, surface features, internal structure, and more than forty additional optical properties provide a history of the particle and its source. It requires a microscope capable of examining a single field of view with transmitted brightfield, darkfield, linear polarized light, crossed polarized light, circularly polarized light, and reflected darkfield illumination in sequence and together without moving the slide and doing so in seconds.