A method and system for observing and monitoring thermal characteristics of a machining operation, such as a surface finishing operation, performed on a workpiece is disclosed. The surface finishing operation can be performed on the workpiece in order to remove a surface defect, e.g. a parting line, on a surface of the workpiece and/or to provide a mirror-like finish to the workpiece. In one embodiment, an emissive layer is applied to the workpiece to increase a thermal emissivity of the workpiece. In some embodiments, a finishing surface, such as a polishing or buffing wheel, and/or a lubricant used in a finishing operation is monitored. A thermal profile of the surface of the workpiece, finishing surface and/or lubricant can be obtained. The finishing operation can be modified in response to the monitored thermal characteristics to prevent the occurrence of defects and improve the efficacy of the finishing operation.