Abstract: Temperature measurements are critical in gas turbine engine design but difficult to obtain due to the extreme environment. Temperature indicating paints (thermal paints) have been used for decades to map maximum temperature fields on superalloy components but have numerous weaknesses. Disclosed herein are novel glass ceramic thermal paints that undergo viscous flow sintering to indicate temperatures up to 1000° C., with high resolution (±5° C.), by an optical transition. Disclosed paint formulations are designed to adhere to Nickel-based superalloys or SiC—SiC ceramic matrix composites (CMC) by closely matching coefficients of thermal expansion and may function for times above 60 hours. By utilizing automation and a UV:VIS spectrometer, quantitative temperature maps can be generated for easy comparison to theoretical models. A transient sintering energy model is disclosed to recover full thermal history information.