Fully or partially metal-coated microspheres are often used to create a conductive or retroreflective surface while taking advantage of precise spherical shape and controlled particle size of microspheres. Metal coatings on glass (solid and hollow) and polymer core spheres are available. There are numerous research articles based on work with metal-coated microspheres.

Metal-coated microspheres were developed to produce electrically conductive coatings that can be added to tiles, fabrics, adhesives, sealers, plastic, rubber, composite and resin materials. When added at appropriate ratios, these materials provide electrical conductivity and shield electronic devices against EMI. Low particle density and a large surface area facilitate slow phase separation in paints and adhesives compared to heavy metallic and inorganic fillers.

Metal-coated microspheres also offer unique advantages as PIV tracers and seeding particles for flow visualization applications that require densities below or above the density of water. The true particle density of the seeding particles is precisely controlled with the density of the core sphere (solid or hollow glass) and a thin metal coating that adds a highly visible reflective surface.