Determination of the water stain formed under standardized conditions in engobes compositions or on ceramic tiles for coating. The analyses are carried out after immersing the samples in water for standardized periods. The color differences detected in the samples after the immersion procedure are evaluated using the colorimetric parameter ΔE*, determined using a reflection spectrophotometer. The results are useful for evaluating the performance of ceramic engobes compositions and are also considered as a quality parameter for ceramic tiles, in accordance with the ABNT NBR 15575:2013 standard – Residential Buildings — Performance.