mordant Archives - Botanical Colors

Mordant Monday: What is Dunging?

Cellulose fibers are the most common fiber that we start with as cotton fabric is readily available and affordable. However, cotton does not have the same affinity for natural dyes as protein fibers such as wool, so the cellulose mordant process is different to achieve good results. The mordant process for cellulose fibers includes pretreating with a tannin, then immersing the tannin treated fabric into an alum solution. This method is one of the earliest mordant methods for cellulose fibers and produces very good results. We use this method regularly as we also love to experiment with different tannins to … Read more

MORDANT MONDAY: Can A Cold Water Mordant Deepen Colors?

We get mordant questions all the time at Botanical Colors so why not create Mordant Monday??? Got mordanting questions? Email [email protected] YOU ASKED: I recently purchased some aluminum triformate from you all. I tried the aluminum triformate using it at 10% WOF hoping to get the strongest results possible. So far I have only the aluminum sulfate to compare it to. It seems the aluminum sulfate samples are much darker, especially the reds, although I am not finished with all the colors. I am wondering if this is typically the case? Is there anything you would suggest to coax … Read more

Twilight Tannins with Cara Marie Piazza (Formerly Tannin Grayscale) – March 16th

Description Twilight Tannins Online workshop with Cara Piazza Formerly called Tannin Grayscale MARCH 16TH, 2025 10AM PST / 1PM EST The workshop will be recorded and available for 180 days after purchase. The backstory: Cara is famous for her moody, New York state of mind color palettes, and the tannin mordanted fat quarters are perfect for showing off these rich shades with subtle colorations and unusual hues. We called her workshop “Tannin Grayscale” as a nod to graphic designers who will add a touch of gray to a color in order to create a more vivid hue. However, now that … Read more

Mordant Monday: Tannin Workshop Review

Mordanted fat quarters in iron, marigold, indigo, marigold+indigo, logwood, logwood+ indigo, logwood + marigold and logwood + marigold+ indigo. Both Cara and I taught new online workshops about tannins and natural dyes this month. Cara introduced Tannin Grayscale, a fascinating look into using iron and tannin to create a rich range of deep and moody neutrals. I had envisioned that this would be a workshop on gray, gray and more gray, but the surprise was that her techniques create some beautifully saturated shades. My workshop was Tannin Rainbow, where I concentrated on combining different tannin mordanted fabrics with natural dye … Read more

Mordant Monday: Tannin Extravaganza!

TANNIN A TIMELESS MORDANT For Today’s Mordant Monday, we are highlighting all things tannin. Tannins are a bitter and astringent compound found so abundantly in many plants. In food, they serve as the slight pucker in black coffee and tea, and the “oaky” flavor in aged wines. Tannins are used in medicine and for leather tanning. For us, they are the natural dyer’s not-so-secret-weapon to beautiful color. For the natural colorist, tannins provide a rich base for unusual and eye-catching combinations, and they’re particularly effective on plant fibers such as cotton and linen. We have a variety of tannins for … Read more

A Nerd’s Guide to Mordanting at Sanborn Mills

A Nerd’s Guide to Mordanting at Sanborn Mills This is the nerd’s guide to mordants – what they are, why they are important and how they are used in natural dyeing. Everyone wants to create long-lasting and beautiful plant color and the best way to do that is to mordant properly. The class will experiment with the most popular plant-based tannins and alum accumulators, mineral salt mordants and other binders to see the effects on animal and plant fibers. Each mordant variable will be dyed so that we can see results and we will build a reference folio for students to … Read more

More Mordant Experiments

I’m obsessed with using tannin and aluminum sulfate to create different color bases for both natural dyes and indigo. What I love about this technique is that this is a great mordant option and it’s a lot of fun to see the colors develop and take on the subtle differences between the different tannin bases. This time, we’re working with a lightweight, pre-mordanted, organic cotton suitable for stitching and quilting. We mordanted 4 fat quarters, each with a different tannin, and then tried a few dye experiments using Marigold Mix, Madder extract and Indigo. Start with our Mordanted Fat quarter … Read more

Mordant Monday: Middle Mordant Magic

In this week’s Mordant Monday, we discuss Middle Mordant. Middle Mordant is a technique that I learned about from The Art and Science of Natural Dyes. It’s considered to be a Japanese technique and is a simple way to create rich color on silk. Middle mordant uses room temperature dye baths and you can repeat the process until the fabric is the color you want. The purpose of middle mordant is to deepen the depth of shade and most of the examples I’ve seen use silk fabric and alum mordant. There are somewhat similar techniques that old dye books discuss, … Read more

Mordant Monday: Sneak peek of a new product

Mordanted Sashiko Thread with Different Tannin Options! Now you have the convenience of using tannins and a pre-mordanted thread to create your own color palettes and who doesn’t love that? Pictured from Left to Right: Cutch and Alum mordant, Sumac and Alum mordant, Gallo-Tannin and Alum mordant, and PFD, unmordanted Sashiko Threads We’ve been busy adding to our very popular mordanted product line, and will be offering mordanted Sashiko threads using three different mordant variables. The light brown color is Cutch, a light brown tannin, the yellow is Sumac, a yellow-based tannin, the light cream is Gallo-Tannin, a “clear” tannin, … Read more

MORDANT MONDAY: Tannin Mordanting Cotton & Stiff Wool

We get mordant questions all the time at Botanical Colors so why not create Mordant Monday??? Got mordanting questions? Email [email protected] YOU ASKED: I’m getting ready to dye vintage cotton runners. I have aluminum acetate, which tannin powder would you recommend? Weight of fiber protocol?I have a bag of wool roving and also trying to figure out the best way to handle. Last time I ran it through a dye bath it dried dull and stiffish. What do I need to do next? KATHY ANSWERED: The choice of which tannin is really up to your preference. We like to use … Read more