I decided the obvious way to test for washfastness was to wash. So I embroidered with the plum pine fruit–no mordant–silk thread, and with the plum pine fruit-with alum and cream of tartar on a piece of cotton… and added a little eucalyptus dyed silk thread for good measure. Not the best example of embroidery ever seen, but it will do the job. The two upper examples were purple (like the thread on the cards) when they went into a normal wash–30C with eco-detergent. One wash later, the no-alum sample is grey and the with-alum sample is green-grey. Eucalyptus shows its true colours yet again.
Yesterday I tried washing my sample cards at 40C with eco-balls (we have laundry variety here, as you will shortly understand) and they were still purple when they came out of the wash. Interesting… this made me wonder if part of what is going on here about Ph. Detergent would be more alkaline than eco-balls.
After 4 more washes:
You might remember that I did some darning with my early silk samples. They have not fared well either–but the mending is still doing the job! The pink is still pink, but much faded after what I would guess as being about 8-10 washes. The purple is blue, and paler.
I knit some test samples from my yarns. They fared better, washed with other woollens, cold with soapnuts rather than detergent (if anything, a slightly acidic wash). The sample on the right has two shades of plum pine with alum and CoT on BWM alpaca rich, with a band of cotton used to tie the skeins in between because this yarn took so much colour during the dyeing I was curious. The sample on the left has two shades of plum pine on patonyle (wool and nylon superwash sock yarn and a sample of handspun Wensleydale). One has gone from purple to grey and the other from purple to blue. Blue? Before:
After, with unwashed BWM Alpaca Rich in the background for comparison.
Well then. Not what you’d call really excellent washfastness. And some new mysteries to ponder, as usual.