I found these Cortinarius semisanguineus when I was foraging with my friend Hannah in Vermont. They were very mature and well drenched from the massive rain storm we found ourselves in. With these Corts. the red color is in the caps, you can visually see it and it is very easy to distinguish from the orangish color in the stipe. I separated the caps from the stips and only used the caps when they were fresh. I modified the dye bath with sodium carbonate to pH9 and to help the color bloom I added 1% calcium carbonate to the dye bath. This is a trick you do when working with Madder to get the color to be more red than orange so I thought I would give it a try. Much to my delight it all worked and I received a range of reds and the lake responded very well!
I have found that the Cortinarius dermocybes tend to be very sensitive to hot water. I used hot tap water which was around 110 degrees and added the ground mushrooms to the water. I did not cook these mushrooms or increase the temperature. I simply let them sit in the water for an hour and it eventually cooled to 85 degrees, strained the dye bath and dropped in the fibers.