Just as the name implies, a mirror coating is highly reflective making the wearer look brilliant and gleaming.
Only those looking at the person wearing the glasses can see the color of the mirror coating.No matter of what color the coating is,mirror coatings are purely cosmetic and are available in an assortment of colors and the wearer perceives no difference in vision .
Mirror lenses are good for situations that require a reduction in the overall brilliance of light, such as sunlight on snow. They reflect light away from the eye (beyond the standard absorption of a tinted lens) which is ideal for people who are light-sensitive.