Due to the low and close melting and sublimation temperatures (340 and 350 °C, respectively), the crystal growth of selenates and/or selenites is generally achieved using either chemical vapor transport routes, hydrothermal methods due to the good solubility and reactivity of (SeO3)2− anions or isothermal evaporation synthesis. Here we report examples many new crystal structures obtained using these synthesis routes. Particularly, description of each process is given with theoretical and practical information assorted with description of selected structures.