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Refractory bricks are essential for high-temperature applications in various industries. The fabrication of most of our daily life products consumes a certain amount of refractories. Although essential, they are often not perceived so by the public. Depending on their specific application and the position in the furnace, different types of refractories are necessary. The different types consist of a small number of naturally occurring high quality raw materials, such as dolomite, magnesite, bauxite and chromite. These raw materials have to meet strict quality specifications and account for 40 to 50 % of the refractory costs. Currently, most of the spent refractory bricks are used for low-value applications, such as construction material, or landfilled. Therefore, reusing refractory bricks to substitute new raw materials in the production of refractory bricks holds large potential for adding value. Due to the variety of different brick types, the used refractories usually do not meet the strict specifications of those for new raw materials. Thus, it is necessary to sort the spent bricks into categories according to their type. A useful tool is the sensor-based sorting (SBS) technology. SBS is has been used in mineral processing for more than 30 years and is gaining more and more significance. To be able to use SBS to separate the different brick types it is necessary to find a suitable sensor, which can distinguish between the different brick types. This paper describes several tests with various sensor types to evaluate the possibility of SBS for spent refractory brick separation. The tested sensors include conventional sensors, such as near infrared spectroscopy and the promising LIBS (laser-induced breakdown spectroscopy) technology. All results were obtained within the European FP7-project REFRASORT, which aims to develop an automated sorting equipment for refractory bricks.