There is definitly a lighter than navy dupioni. Have a look at Draper's. Flusser had this one. He had three shades of dupioni: tan, elephant gray, and a slate/AF blue. I really, really wanted the latter. Alan wore it in the shop the day I tried to order it. He talked me out of it. Said it was impractical. A Palm Beach/man of leisure suit. I never forgot it, and eventually got a similar color in mohair.