This progress report covers continuing work to develop a temperature probe for a coal gasifier. A workable probe design requires finding answers to crucial questions involving the probe materials. We report on attempts to answer those questions. We designed, assembled, and tested a portable test fixture that can give relative quantitative data on the condition of phosphors. It needs a more-sensitive detector for optimum performance. We ordered an appropriate detector. An experimental test of the survivability of thermographic phosphor in an ambient environment similar to that in a slagging gasifier showed no substantial deterioration of the phosphor. We consider this result so important that we delayed the date of publication of this report by one month to accommodate it. We assembled the first version of a prototype probe and were preparing to test it at the time of this report.