Asbestos minerals have Crystal Patterns with in them that under polarized light show unique optical properties. These properties can be used to identify asbestos in building materials. Light microscopy has been used for well over 100 years for the determination of mineral species. This analysis is carried out using specialized polarized light microscopes(PLM). Polarized light is a contrast enhancing technique that improves the quality of the image obtained when compared to other techniques. Polarized light microscopes have a high degree of sensitivity and can be utilized for targeting a wide range of specimens. PLM is perhaps best known for its applications in the geological sciences, which focused primarily on the study of minerals in rocks within thin sections. The identification of minerals is an ongoing process with many new minerals describes each year. Minerals consist of atoms that may be arranged in random order or in a regular arrangement. Amorphous materials have atoms in random order while Crystalline minerals have long-range order. Many materials are transparent to light, at least for small particles or in thin sections. The properties of these materials can be investigated by the effect that the material has on light passing through it. The six asbestos minerals are all crystalline with particular properties that have been identified and cataloged. The EPA method for determining asbestos in bulk building materials requires a great degree of sophistication on the part of the microscopist. The microscopist's accuracy is enhanced by experience. This is usually accomplished through substantial on-the-job training as well as formal education in mineralogy and microscopy. Michael Manning the owner and director of Asbestos Identification Laboratory has a Bachelor of Science Degree in Geology, has completed many courses in advanced microscopy and has 20 years experience analyzing asbestos samples using a polarized light microscope.