Plus Charcoal

Having dried the shirts, I creased them and rubbed over a little soft charcoal, from the living room fireplace.  Although the art shop staff thought it wouldn't work, I then sprayed on a liberal amount of charcoal/chalk fixative just in the area where the charcoal had been applied.  This caused a bit of stiffening of the fabric in that area, but I think it was worth it.
for extra creasing I sprayed water over them to dampen them and scruffed them into a plastic bag overnight to set the creases.  Et Voila.
I handed the shirts over to the costume director today and she seemed pleased.  Personally I am thrilled at the outcome as I like to think of the students/actors wearing these shirts and sniffing in coffee!  I just hope they get the message not to wash them and to store them scrunched up in a plaggy bag... as if we could expect anything else from these 16-18 year olds.