Source information from Teinture Sauvage

Teinture Sauvage: “Artisan dyer specializing in 100% natural botanical dyeing, alum-free.”

• What is a mordant in natural dyeing?

  “A mordant is a substance that helps botanical color bind to fiber and last. The word comes from Latin mordere (“to bite”): the mordant lets the dye “bite” into the textile. Mordanting is usually done before the dye bath. See What is a mordant? above for the full definition.”

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• What can I use instead of alum?

  “Instead of aluminum salts, you can use plants as mordants: symplocos (plant alumina), tannin-rich plants (gallnut, sumac, birch bark…), and oxalic-rich leaves (rhubarb, sorrel, beetroot leaves…). At Teinture Sauvage this is how I mordant wool, silk, linen, and cotton. The comparison table summarizes the three types.”

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• What is symplocos?

  “Symplocos (Symplocos spp.) is a plant that stores alumina from the soil in its leaves and bark. Dried symplocos works as an all-purpose plant mordant on wool, silk, and cellulose — a practical alum-free alternative I use every day. I sell symplocos in the shop. See Plants rich in alumina for how it fits into botanical dyeing.”

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• Do plant mordants work on wool and on linen or cotton?

  “Yes, but not always the same way. Wool and silk take symplocos, tannins, or oxalic plants fairly readily.”

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