The Black Mirror, also known as Speculum Sine Macula.

This appears to be an extremely obscure subject. This "mirror" has been depicted for centuries. Only it is depicted as black. Artists in recent times always draw mirrors either realistically or to the overall color of its surroundings to emulate the actual behavior of mirrors. Depicting a mirror as black raises some red flags. It implies that it is not a mirror.

The black mirror was an object that appeared to be very dark when inactive, and showed something quite interesting when active. Looks like you can see through it into other black mirrors.

This object is repeatedly shown in old world art in the same fashion. What is the mainstream excuse for "mirrors" being depicted like this? These objects are obviously seen as divine/sacred and they are shown to be the center of attention in many cases. Why is the mainstream so quiet on this subject?

And for the love of God, let me know if you have more information on this. (1/8)