bonanza /bə-nanˈzə or bəʊ- or bo-/

1. A rich mine or vein of precious ore (N American)
2. A large amount of (usu) silver
3. Any source of wealth or stroke of luck

Very prosperous

• unaccredited
• unaccusable
• unaccusably
• unaccused
• unaccustomed
• unaccustomedness
• unachievable
• unaching
• unacknowledged
• una corda
• unacquaint
• unacquaintance
• unacquaintances
• unacquainted
• unacquaintedness
• unactable
• unacted
• unactive
• unactuated
• unadaptable
• unadapted
• unaddressed
• unadjusted
• unadmired
• unadmiring