In this study, pure and Co-doped lead tungstate (PbWO₄) and calcium tungstate (CaWO₄) nanomaterials were synthesized using the coprecipitation method at room temperature. The structural properties of the prepared materials were analyzed using X-ray diffraction (XRD), confirming a single-phase tetragonal scheelite-type structure for both undoped and Co-doped samples. Optical properties were investigated through UV-Visible spectroscopy and photoluminescence (PL) spectroscopy, while the magnetic behavior of Co-doped PbWO₄ and CaWO₄ was examined using a vibrating sample magnetometer (VSM). The incorporation of Co into PbWO₄ and CaWO₄ led to variations in the optical band gap, which were determined using UV-Visible diffuse reflectance spectroscopy (DRS). A distinct blue emission was observed for both undoped and Co-doped CaWO₄ nanomaterials. Additionally, paramagnetic behavior was exhibited by Co-doped PbWO₄ and CaWO₄ nanomaterials. © 2025 Elsevier B.V., All rights reserved.