Hi,
The hat is really wonderful! I cannot make out the label, but it looks like Miss Mary. Miss Mary is not well known to many folks, but she is one of my all time favorite milliners. My brain is foggy right now, but I do know her actual full name. I would date your hat to the early 1950s. It does not seem to be a specific style, but you could call it a cocktail hat or a dinner hat. I have quite a few Miss Mary hats in my collection, and especially love her black hats and black velvet hats. She was a master with black velvet. Her workmanship in the early 1950s was excellent and very fine quality. I think her hats are what you might call "sleepers" that will rise in value in later years.
Miss Alice was another good milliner, does it say Alice or does it say Mary?
I love your hat!