Dear of troy and Jackie, thank you for that information. I remembered being taken to a silk worm farm once when I was a boy and could not imagine from what I remembered how it would have been possible to dye the individual threads for this type of material (dupion silk) in two different colours. From what you have supplied it seems that the twin thread is really coincidental to the two colours. The material could equally well be one colour, or a non-dupion silk could have threads dyed different colours. The real distinction of the dupion silk is the natural variation in thickness.