The technical ceramics of the Bronze Age Krotovo culture of the Baraba forest-steppe (the end of the III - the beginning of the II millennium BC) were analysed. Samples of internal and external surfaces of casting molds and crucibles were measured by thermogravimetric analysis. Good and very good quality of firing was identified. Reliable differences in the mass loss were identified between the inner and outer surfaces of the crucibles, which allows determining the type of fire installation (open or closed), the direction of air injection onto the crucible, and the period of use. Other processes occur in a mold. During metal pouring, a large gradient of temperature arises: at the surface of contact with the casting, mold temperature approaches the temperature of the melt. At the outer surface, temperature is equal to the initial level at this moment. However, the time of temperature action is short-term and limited by the period of metal solidification. The difference in the mass loss between the inner and outer surfaces can get accumulated only in the case of a long-term use of the mold, and thus it provides evidence of how many times the mold was used. Determination of the functional differences between technical ceramics, crucibles, and molds can be made on the basis of differences in mass losses for the inner and outer surfaces. The results of thermogravimetric analysis add essential objective data to the solution of the question of the multiple uses of forms and, as a result, the reconstruction of the technology of the ancient bronze casting production in Eurasia.