For Sale: Maurice Tempelsman’s Manhattan Penthouse

Maurice Tempelsman, the Belgian-born diamond magnate, financier, and political insider who shared a 14-year companionship with Jacqueline Kennedy Onassis after the death of her second husband, Aristotle Onassis, spent the final chapter of his life in a Park Avenue penthouse with nearly 3,600 square feet of wraparound terraces.

Tempelsman, who died at age 95 in 2025—roughly 31 years after Kennedy Onassis—paid $3.3 million for the two-bedroom aerie in 1999, according to…