"Eat organic, save the planet—it's that simple," said Annie Lennox at Thursday night's Feast of Albion ball, which fêted the efforts of Britain's organic food industry. The extravagant eco-banquet was sponsored by Quintessentially, the lifestyle group run by Camilla Parker Bowles' gregarious nephew Ben Elliot, and that certainly didn't hurt the turnout. London A-listers including Mick Jagger, L'Wren Scott, Sophie Dahl, Trudie Styler, and Colin Firth tucked into nettles picked from Hyde Park, wild fennel foraged from the banks of the Regent's Canal, venison from Windsor Great Park, and, in a carbon-footprint protest, root vegetables cycled in by teams from an organic farm some 50 miles away. "I hope I don't have an allergy to nettles," joked Styler. We just hope she was able to laugh off the fact that she showed up in the same Roland Mouret dress as socialite Jemima Khan.

A few time zones away, the Frick Collection's Young Fellows Ball drew the princesses of Park Avenue and the Wall Street suits who love them (and who will even put on a brave face and pretend they wouldn't rather be home watching TV). This year's theme, a masquerade, was a party photographer's worst nightmare, as plenty of socials went virtually incognito behind elaborate masks. After paying their respects to the evening's honorary chairman, Elie Saab, many guests bypassed the hors d'oeuvres and Champagne in the courtyard and made a beeline for the museum's art-filled corridors. Ivanka Trump, meanwhile, was as intrigued by the building itself as its contents. "Why do I like this museum? Well, there are few buildings in New York that have a frontage on Fifth Avenue or a courtyard such as this," said Trump, sounding every bit her father's daughter. "Not many people would give you that answer, but I'm a real estate person."