What Is The Color Of A Mirror?

When staring at your reflection in a mirror, you probably see a spectrum of colors. However, what you may NOT see is the actual color of the mirror. Is it white? Silver?

Well, before we ponder that, we need to understand how colors work. Color is essentially how our eyes perceive reflected light. Our eyes are specifically tailored to a type of reflection known as diffusion reflection, where the light arrives at our eyes from a variety of angles.

However, certain smooth surfaces are capable of specular reflection. During specular reflection, all of the photons of light are directed in the same direction and angle. This form of reflection is what we see in the mirror. Essentially, mirrors construct images based on what light source they are exposed to.

But what does this have to do with the color of a mirror? Most mirrors are composed of a soda–lime silica glass substrate and a silver backing. The combination of such metals produces an extremely faint hue of green. This hue is so light that it cannot be perceived by the naked eye unless when viewed through a “mirror tunnel” (mirrors reflecting each other).

References: 

http://io9.gizmodo.com/what-color-is-a-mirror-1725115120

http://www.sciencefocus.com/qa/what-colour-mirror