The black pigments used in Late Period (11th–17th centuries) painted pottery in the Yocavil Valley were characterized. Changes and continuities in the composition of this material over an extended span were evaluated. A regional sample of 47 potsherds from the Loma Rica, San José, and Santa María styles was collected, and for the first time micro wide‐angle X‐ray scattering was used in these ceramic styles. The results indicate the simultaneous presence of iron oxides (hematite) and solid solutions of manganese and iron oxides (jacobsite–magnetite). Besides, the paints were prepared by mixing the pigments with clay‐based binding materials.