A scanning electron microscope (SEM) is an analytical instrument that uses an electron beam to scan over an area of a specimen’s surface and produces an image from electron-electron surface interactions. SEM images can be produced from two types of electron sources: (1) secondary or (2) back-scattered electrons. Secondary electron (SE) imaging allows for the characterization of a specimen’s topographical features due to the large depth of field and high magnifications (up to 200,000X) associated with an SEM. Back-scattered electron (BSE) imaging allows for characterization of a specimen’s elemental composition as the intensity of a BSE image is strongly dependent on to the atomic number (Z) of the area under analyzed; BSE imaging allows for identification of elemental changes at the surface of geological, metal, plastic, and ceramic specimens. The interaction volume (IV) from a specimen’s surface that produces the different signals that can be created and detected by an SEM (such as SE, BSE, and characteristic X-rays) is approximately 1 cubic micrometer in size; as a result, scanning electron microscopy is considered a surface analysis technique.