The study concerns site no. 89 (the second half of the 13th and the 14th century), although no techniques and vessel shapes typical of the late Middle Ages are present in the local industry, these being introduced together with settlement on German law. Finds of glazed pottery from the potmaking settlement take on particular importance in the context of studies of manufacturing techniques. Thirteen pottery kilns were found on the site; five of these can be connected with the making of glazed ceramics, including vessels and floor tiles and a unique set: 600 fragments of crucibles for melting glaze and other groups of vessels, represented mostly by waste products left-over from the firing of pots and the glazing of fired products. All the vessels were made by coiling technique and then carefully turned on the wheel. The melting of glaze in crucibles - which were made by cutting vertically through large bulbous vessels executed in the coiling technique - took place in furnaces found in the settlement. The use of clay of loess origin resulted in frequent breaking of the vessels at the joining and the surface was often flaking. The edges resulting from the cutting were either burnished or inwardly beveled, and hollows were made in the still plastic clay at the edge making it possible to move the crucibles holding the hot liquid glaze. The glazing process required the fired pot to be dipped in the melted glaze in the crucible or the glaze to be poured over it. The crucibles were used repeatedly, as indicated by numerous layers of congealed glaze. Point analyses of chemical composition with an X-ray fluorescent spectrometer combined with scanning microscope were carried out of 62 fragments of vessels and floor tiles and demonstrated that the crucibles were made of ferruginous clays of loess origin, while the ceramic mass made from these clays did not differ in mineralogical and chemical composition from the remaining ceramic finds, including unglazed kitchen ware. Chemical composition analyses of the glazes revealed usage of a lead-silica recipe, colored solely by a ferric oxide. The basic glaze component content for all product categories recorded in the settlement was very similar, with the exception of ferric oxide (Fe2O3), concentrations of which in some glazes exceeded 10% by weight. These glazes were distinguished by a black-brown color with silvery shine. The manufactured vessels represented the tableware that was distributed throughout the castle and on other sites in the area of Przemysl. Being a luxury product, it found customers among the social elites, including presumably the Ruthenian princes. A rich range of vessels were made, primarily jars with handles, but also vessels with polygonal handles, bowls, cups, lids, often richly decorated, pans and zoomorphic ceramics of a function difficult to determine. Some cooking vessels were accidentally glazed in the process of glazing other products. Summing up, the site is a unique in Polish territory as the workshops operating in this spot mass produced floor tiles and glazed vessels. The origins of this branch of production on the site should be traced to centers connected with the Rus' principalities, although there is no lack of local trends in this pottery, especially in its style. 20 Figures, 3 Tables.