Abstract PbS quantum dots arranged in a 3D-structure with sufficient regularity as a photonic crystal is constructed by a self-ordering of PbS coated close-packed glass spheres. The minimization of the electrostatic energy of the individual PbS molecules facilitates the preferential growth of PbS at the points where these glass spheres touch. The striking regularity of the distribution of these PbS quantum dots constitutes a man-made crystalline structure of PbS quantum dots in the matrix of glass spheres. The concept presented here combines properties of two technologies that have been the focus of attention in recent years, namely: photonic crystals and quantum dots (QDs). This combination will produce a new material with unique and highly desirable optical properties that have never been found in bulk solids.