Ca3ZnSe4 is Lavarevi\'{c}ite structured and crystallizes in the cubic P-43m space group. Ca(1) is bonded to four equivalent Se(1) atoms to form CaSe4 tetrahedra that share corners with four equivalent Zn(1)Se4 tetrahedra and corners with eight equivalent Ca(1)Se4 tetrahedra. Zn(1) is bonded to four equivalent Se(1) atoms to form ZnSe4 tetrahedra that share corners with twelve equivalent Ca(1)Se4 tetrahedra. Se(1) is bonded to three equivalent Ca(1) and one Zn(1) atom to form corner-sharing SeCa3Zn tetrahedra.
Ca3ZnSe4 is Lavarevi\'{c}ite structured and crystallizes in the cubic P-43m space group. Ca(1) is bonded to four equivalent Se(1) atoms to form CaSe4 tetrahedra that share corners with four equivalent Zn(1)Se4 tetrahedra and corners with eight equivalent Ca(1)Se4 tetrahedra. All Ca(1)-Se(1) bond lengths are 2.84 Å. Zn(1) is bonded to four equivalent Se(1) atoms to form ZnSe4 tetrahedra that share corners with twelve equivalent Ca(1)Se4 tetrahedra. All Zn(1)-Se(1) bond lengths are 2.54 Å. Se(1) is bonded to three equivalent Ca(1) and one Zn(1) atom to form corner-sharing SeCa3Zn tetrahedra.