Are interesting because they keep some of their light-sensitive properties and can therefore appear to be washed out over time. this condition can be reversed, however, by returning it to a dark room.

Shadows  because they are light sensitive

It depends on what type of third separates the three notes.for example: if you have two mayor thirds is an "aumented chord"if you have two minor thirds is an "diminued chord"if you have one mayor first and then one minor is a "mayor chord"and inverted is a "minor chord"