I once lost a diamond at a debutante ball!
Really? where you a debutant youself? or a partner for one of them? anyway do you know ballroom dance?
I got dragged to it, but I know a little bit of how to ballroom dance. Do you know anything about the balls?
I know that Ballroom dance is set of partner dances that are practiced socially and competitive around the world.  But I don't know how to do it.
It is an elegant dance. If you can find people that can do it the right way.
It seem old-fashioned to me, like something you would do in 17th century English novel, but it is also practiced on stage, film an TV.
Yeah, seems like a southern thing maybe. But your right I read about it in a lot of novels set long ago.
The debutant dance also seem old-fashioned, but it is sometimes used as a fund-raising event.
I think they still do those kind of things down south. Like the coming out party when you turn a certain age into society.
Well yes, originally the term meant the woman was old enough to get marry.