I don´t think a lot of pottery is produced in the Madrid region . Most pottery that I see comes from Andalucía .. Sevilla , Granada etc... . There is a souvenir shop on the corner of the Plaza de Cánovas del Castillo .. A short walk from El Prado that has quite a good selection . I actually bought a couple of olive dishes in a cheap store .. Just in very rustic brown and yellow ochre and "Rdo de Madrid" on the side ( touristy but not over the top ) . They have 2 small jars integrated into the dish ... One for "huesos" ( the stones ) , and the other for cocktail sticks . I think they´re great . €2.95 each !