The Diamond chair, designed by Harry Bertoia in 1952, earned him the title of "Designer of the Year 1955" in the United States—and what a revolution it was! Its almost ethereal structure, made of steel wires welded by hand, one by one, combines elegance and lightness for an unforgettable, timeless look! Like a curved diamond, the Diamond chair, produced by Knoll, has never lost its modern appeal. We have three black Diamond chairs dating from the 1960s. Knoll only began signing its chairs in 1992, so these chairs are unbranded but are authentic.