Old standing mirror home furniture

This mirror is in a room that has not been used or cleaned for a very long time. I wanted to find out what the best way to clean the woodwork on it is before I do something stupid.

I can not find anything similar to it in my research and am not even sure what to call it other then a dressing mirror. Any opinion on what it is, age, style, value would be appreciated. What I imagine probably hurts it's value it is over 9 feet tall so would not fit in most modern houses with 8 foot ceilings and the mirror has a lot of black spots so would need to be resilvered which I assume would be very expensive on such a large piece of glass.

I'm trying to clean out the room and need to do something about all the dust so I was just going to ask a general question about cleaning antique furniture but my friend was over and he made such a big deal about the mirror that now I'm very curious.