Optical Microscopy

Optical microscopy offers several advantages over SEM that makes it a favored technique for forensic work and concrete petrography. The image is viewed in full color and generally at a lower magnification, thus making it a more suitable technique for observing features at the millimeter scale and larger. Thin-sectioning and fluorescent microscopy techniques can be used to clearly illuminate chemical attack and crack features. Optical microscopy is also a useful technique for observing clinker phases. [A good reference book is “Microscopic Examination and Interpretation of Portland Cement Clinker, SP030” by Don Campbell, available from Portland Cement Association.]