Quote - a real mirror is a glass over  ???  i've never looked to see what was behind the glass in a mirror.  silver?

the light reflections should bounce off what's through the glass. 

oh wait, Alice is through the looking glass.

A glass over aluminum, usually. Aluminum is an extremely high reflector - more than just about every other affordable metal and even more than silver, when it is done right and sealed against contact with air.

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Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)