I think we do. The size and distribution of particles produce Carey Lea silver which is yellow to red for instance. It is necessary to have effects that are specific to some portion of the visible spectrum to see a color, and most collections of particles have a wide size distribution, but not all. Aperiodic location aids visualization of the so-called plasmonic effect. Periodic order produces diffraction patterns that are independent (mainly) of particle size. Resonance (like quantum dots) and Mie scattering both contribute to color but are different in principle.

http://microphonium.blogspot.com/201...d-patents.html