The effective scattering cross sections for metal spheres have been measured through the resonance region, using wavelengths between 0.45 and 15 microns. Spheres of iron and copper sorted into reasonably narrow diameter distributions between 2 and 20 microns were supported in layers on Pliofilm and silver chloride. The results are given in terms of the scattering area coefficient k (the ratio of scattering cross section to projected area of the spheres) as a function of α(the ratio of sphere circumference to the wavelength used). These results are in general accord with qualitative predictions based on the Mie theory. Detail in the resonance region is obscured by the finite diameter distributions of the samples.
E. LYNN CLEVELAND and RICHARD C. RAYMOND, "Scattering of Visible and Near Infrared Radiation by Layered Distributions of Small Metal Spheres," J. Opt. Soc. Am. 42, 183-185 (1952)