We get mordant questions all the time at Botanical Colors so why not create Mordant Monday??? Got mordanting questions? Email [email protected]
YOU ASKED: For plant fibers I was taught to use aluminum acetate for the mordant and then rinse in calcium carbonate to neutralize the acetate. That extra step is minor, but I’m wondering whether aluminum acetate is a better mordant than aluminum sulfate. It sure is more expensive!
KATHY ANSWERED: Yes, that is the mordant process that we use as well. I don’t think that aluminum acetate is necessarily a better mordant, but it does have some strengths over aluminum sulfate mordant. Specifically, we find that our colors are brighter with aluminum acetate when compared to tannin and aluminum sulfate, and also with aluminum triformate. Tannin plus aluminum sulfate makes a very good, strong mordant and it is a little less expensive. As an artist, you have the flexibility to experiment with and vary these mordants and see what works best for your practice.
If you are looking to save money, alum-based mordants, including aluminum acetate baths may be reused several times before discarding it by refreshing the bath with a small amount of additional mordant. Tannin baths may also be reused.
You might also want to read:
MORDANT MONDAY: How To Reuse A Tannin Bath
5 Tips to Make Natural Dyeing (More) Environmentally Friendly
Vintage FEEDBACK FRIDAY (2018): Using Calcium carbonate to bloom madder