Then California governor Ronald Reagan wears a suit of silk dupioni in the photo, and that is something seen all too infrequently these days. Dupioni used to be for summer, but is better for warm spring and fall, which means it is just coming into season. Ten ounce (300 gram) cloth with a tight weave, it wears too warm for the depths of summer but is perfect for moderate temperatures.
The principal reason to consider dupioni for tailored clothing is for the surface interest of its slubby texture. Dupioni is woven from the threads from two different silk worms that spin their cocoons close together. The fibers get tangled up and the resultant thread is rougher than regular silk, with bumps and irregularities where the fibers from the two cocoons are combined.
The challenges with dupioni are its cost, which is comparable to linen, and finding the stuff in suiting quality in the first place. When I asked Thomas Mahon to make up an elephant gray dupioni double breasted last year, he told me he had never sourced a length. I have not thought to ask but since he has said nothing about it I am hopeful that his version of Mr. Reagan's suit will be ready for fitting later this fall.