Was your romantic partner one of the world’s 70 ultra-high-net-worth individuals invited to that Valentine’s Day auction for the N.W.T.’s 78-carat Ekati Spirit diamond? Don’t worry if they haven’t given it to you yet. Maybe they just haven’t decided whether to put your new $6 million, 21mm rock on a wedding ring or blingy hip-hop chain for you. Or perhaps your love interest is working on something unique for you with the private jewelers at Tiff…