Tin is a metal that combines several desirable characteristics. It is cheap, non-toxic and resists corrosion. It has, unfortunately, the fatal flaw of being very soft which precludes it from being used in any type of structural application except as a coating.

Its softness makes it easy to polish into a mirror (in fact, this being one of its modern day uses) even though this softness also means that it can dent and scratch easily. You can buff out a hairline scratch but it’ll take great care to prevent dulling an edge. A little extra TLC should keep your six-sided mirror beautiful indefinitely.