# Size of metal domain needed to reflect light ; are small graphene sheets shiny?

I remembered that shininess of a material is because of reflection, ie surface current responding to light. Mathematically, one can solve Maxwell equations under a relevant boundary condition, with plane waves ansatz. This math only corresponds to situations when the size of the metal surface is way larger than the wavelength of light. What happen if the surfaces are smaller than wavelength of say ~600nm light?

What happen for metals that have domains size less than the wavelength? What happen for small graphene sheets whose edges are passivated by hydrogen, and are shorter than the wavelength? If electrons cannot move across different domains that are shorter than the wavelength, can the material possibly be shiny?

There isn't a sharp transition to specular reflection as the size of the reflecting object increases, so the size at which we would say the object is shiny is a matter of judgement. From personal experience mica flakes of around 10 $$\mu$$m and larger look shiny so as an order of magnitude estimate I would say the transition is somewhere around ten times the wavelength of the light.