Metal nanoparticles (Au, Pt, Cu and Ni) were generated in the aerosol phase using spark ablation and analysed for size, shape and number concentration. Particles as small as 1 nm and up to > 60 nm show shapes from fully spherical to fractal-like as characterized by electron microscopy. Furthermore, the metal particles were mixed with TiO₂ nanoparticles, and the number and size of metal particles coating the TiO₂ were determined.