I've seen epergnes plenty of times: they're those structures used at fancy dinners and teas and such, with tiers to hold serving dishes and candles and so on.
But I don't think I was previously aware that such items were called "epergnes." Now I know.

When I was very young, I kept a journal of words I had run across and didn't know. I remember 'epergne' was in it. I'm pretty sure it was from a Jack Vance story. I don't think I've seen it used since.