Traditionally, 75th anniversaries are celebrated with diamonds. The American Ballet Theatre toasted theirs Wednesday night with a gala, sponsored by JP Morgan Chase, that drew an eclectically star-studded crowd to the David H. Koch Theater at Lincoln Center. Alongside more stalwart balletomanes like Fe and Alessandro Fendi, Jamee and Peter Gregory and Adrienne Arsht were Nicole Scherzinger, Alec and Hilaria Baldwin and models like Jessica Stam and Crystal Renn. The evening’s program featured, among other works, After You a new piece from Mark Morris with costumes by Isaac Mizrahi (anyone familiar with the documentary Unzipped will recall Morris’ cameo). After, the crowd retired to the building’s Promenade for dinner, where recently crowned principal Misty Copeland found time for a selfie with Laverne Cox.