Retrieval of temperature emissivity (TE) for targets using thermal infrared (TIR) data is of great importance in climatology, urban heat island analysis, geological studies, and many more. In TIR, water vapor content is the largest source of errors in radiance data (common in humid climate) requiring an efficient atmospheric correction. Another source of error is that the radiance is a function (depend) of the TE of the target, making this an indeterminate problem. The objective of this work is to propose a method to recover TE for quartz from its radiance spectrum measured in a laboratory for mitigating the indeterminate problem. For this purpose, we used linear regression models in radiance laboratory spectrum quartz data, applied to LANDSAT 8 image. The results showed that it is possible to recover the TE with errors of 0.179 K in temperature and 0.0031 in emissivity when compared to other classical methods referred as Reference Channel Method (RCM), and at the same time mitigating the indeterminate problem.