Ag nanoparticles were synthetized in the interlamellar space of a layered kaolinite clay mineral. Disaggregation of the lamellae of non-swelling kaolinite was achieved by intercalation of dimethyl sulfoxide. The kaolinite was suspended in aqueous AgNO 3 solution and, after adsorption of Ag + , the ions were reduced with NaBH 4 . The interlamellar space limits particle growth (d a v e =3.8-4.2 nm); however, larger silver particles may be formed on the exterior surface of kaolinite with d a v e =5.6-10.5 nm diameter. The diameter of the particles prepared in this way is depending on the initial AgNO 3 concentration. The silver nanoparticles prepared were characterized by UV-vis spectroscopy, X-ray diffraction (XRD), Small angle X-ray scattering (SAXS), X-ray photoelectron spectroscopy (XPS) and Transmission electron microscopy (TEM).