WOAD P.S.

During my recent woad-dyeing session, I happened to dye a skein that had been mordanted with alum. I was interested to observe that this alum-mordanted skein dyed a greener, more turquoise shade of blue than the unmordanted skeins. I wondered how I had failed to notice this shade difference before. I can only explain it as follows: Usually, I use unmordanted skeins for indigo & woad dyeing, unless I am using indigo to over-dye a skein already dyed in a dye that requires a mordant. As I always use indigo as the last dye in a 2 or 3-dye sequence, I suppose this was the first time I had used an alum-mordanted skein that had not already been dyed. As to why I always use indigo as the last dye in a sequence – I think this is because the depth of colour from indigo is easier to control than the depth of colour from other dyes. So by using indigo as the last dye, I can dip for a short time initially & then build up the colour gradually. I usually also reserve the other dyebath, in case I need to add some more of the first dye after the indigo (or woad) dyeing process.