Polarised (polarized) light; EM explanation.

[Roodles01]

Facets of a rock specimen sparkle brightly
In terms of electromagnetism how can I show that a linearly polarised light source can be used to determine that the facets are dielectric rather than metallic?

Should have to do with scattering, but not sure whether it could be explained with a dispersion relation, phase speed of light, or . . . . . .


Is there a simple sketch I could produce to show how?

Help, please.
Thank youi

 

[Simon Bridge]

What is the difference between EM wave interactions with a dielectric vs metal interface?

 

[Roodles01]

When an EM wave encounters a dielectric some of the wave is transmitted & some reflected, as with a metal, too.

When encountering a metal the normal part of the EM wave will absorb a small amount of energy, up to the skin depth, but a dielectric will allow the normal incidence of the wave through as a polarised wave whilst the rest will be reflected.

Hmm!
To me this sounds like if I use linearly polarised light normal to the surface of the facets then measure reflection then there would be less reflection from the dielectric than the metal.

 

[Simon Bridge]

... and you didn't need me after all :)