Abstract: An apparatus and method for the measurement of wax appearance temperature and wax disappearance temperature. The apparatus includes the following. The sample receptacle having a receptacle opening, including a bottom, at least one side and an open top. The sample receptacle including an inlet and an outlet for sample insertion and removal. The at least one side about the receptacle opening being light absorbing. The sample receptacle including a transparent cover mounted over the open top. The bottom of the receptacle opening having a reflective upper surface. A thermo device temperature change of the sample. A thermometer to register current temperature of the sample. A viewing chamber above the transparent cover, where the viewing chamber is surrounded by material that is light absorbing. A light emitting device to project light through the viewing chamber and the transparent cover.