This work describes atomic-scale, crystalline structure and size distribution for noble metal nanoparticles produced by water-based, environmental friendly technologies. The process was developed and implemented to produce noble metal nanoparticles to be used in water filters, sensors and cosmetics. The particles were investigated by TEM methods and particle size analysis. Growth process of the crystallites in sols made by chemical reduction in aqueous solutions is discussed. Comparison with growth models for vacuum deposited thin films is also identified.