In February we had a few days of rapid fire snow storms. I shoveled four days in one week (which is a lot for my part of Colorado). I decided to collect some in pots and buckets, and melted enough for a red cabbage dyeing session. Sounds like a lot of trouble, but it was worth it to me because I wanted to see the difference between it and our tap water which is actually derived from snow in the mountains right above my town. I've always heard that our water is very pure because we are so close to the source. It's not traveling great distances or treated extensively. Unfortunately, I cannot find my swatches from the tap water dye bath so I don't have a photograph, but I can tell you there was very little difference between the tap and the snow, which is what I expected.. Here is a photo of the fabric pieces dyed using melted snow. I tried 3 different kinds of silk and vintage cotton and washed the fabric after dyeing. Lost some color but this is what I was left with. I also left swatches of the snow dye in my light filled sunroom for 2 weeks. Those swatches are on the bottom half of the photo. Not much difference. It will be interesting to see the changes given more time as I already know that red cabbage isn't very lightfast. But depending on how one uses the fabric and how much light it will be exposed to, it can still be a good source of coloring cloth. And as India Flint says, you can always re-dye the cloth.
Then I tried water from 2 of the many mineral springs in Manitou. All of spring waters are alkaline in nature and the pigments in red cabbage are very reactive to alkalinity, so I used water from the springs with the lowest alkalinity. Results were striking, as seen in the photo below. Cabbage and water immediately turned this teal green color. Only the vintage cotton mordanted with alum picked up an appreciable amount of pigment. Silks and wool felt picked up little if any pigment. So I am still trying to figure out what happened here. Did the alkalinity and presence of other minerals destroy or make the pigment unavailable? Did the alum help the cotton pickup what little pigment might be available? 
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