A generic method for conductive film coating of minerals and acid-sensitive materials by antimony-doped tin oxide (ATO) is introduced. The coating was performed from a hydrogen peroxide stabilized stannate and antimonate precursor solution. This is the first demonstration of ATO coating from an organic ligand-free solution. Uniform coating of different clays and other irregular configurations by monosized 5 nm ATO particles was demonstrated. The deposition mechanism and the observed preference for mineral surface coating over homogeneous agglomeration of the tin oxide particles are explained by a hydrogen peroxide capping mechanism and hydrogen bonding of the hydroperoxo nanoparticles to the H2O2-activated mineral surfaces.