Back to Mordants and Additives
Glauber’s salt
$4.00 – $7.20
Sodium sulphate. Used as a LEVELLER in both synthetic and natural dyeing.
Glauber’s salt slows down the colour uptake of the dye, encouraging more even and level strike. This is particularly useful when dyeing soft pastel shades.
TO USE: Calculate amount required for 10 to 50% WOF (weight of fibre), lower amounts for softer shades, higher amounts for deeper colours. Dissolve in hot water and add in stages during dyeing, as the bath temperature rises but before dye strikes.
Dispose of spent dyebath in your usual way. Down the drain is fine.
CAUTION: wear a mask when handling powders.
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Citric acid
Used in place of vinegar, as a MORDANT on protein fibres when working with acid dyes or food colouring. Many production dyers switch to citric acid because buying jugs and jugs of vinegar gets too expensive, and vinegar makes your house smell like a pickle factory. Citric acid is odour free!
TO USE: dry crystals may be easily weighed at 5 to 8% WOF (weight of fibre). Follow dye instructions for the recommended acid amounts. Just as with vinegar, the point at which you add the acid to the dyepot can make a substantial difference in the end results. Same goes for hand painting and other methods.
TO MIX A VINEGAR SUBSTITUTE: add 200g (approximately 1 cup) of citric acid crystals to 4L of hot tap water in an empty vinegar jug. Cap and shake well until dissolved. This makes a 5% solution that can be measured and used exactly the same as for vinegar in your dye recipes.
Dye solutions containing citric acid may be safely disposed of down the drain (other than septic systems). Some dyers use baking soda to first neutralize the spent dyebath.
CAUTION: wear a mask when handling powders. Wear gloves when handling citric acid powder, as it can cause skin burns. Avoid breathing fumes (just as with vinegar): dye in a well ventilated area.

Pomegranate, Ground Rind
Powdered/ground rind from the rinds of pomegranate fruits, Punica granatum. NOTE: this is NOT EXTRACT. This is the kind to use if you want to try it as a natural mordant.
We list this as a natural dye, but it is sometimes used as a mordant.
Use on protein or cellulose fibres. Yields soft yellows to green-yellows or gold. Substantive but pre-mordanting recommended. Use at 15-20% WOF for medium shades.
TO USE: soak 24 hours in hot water, stirring occasionally, then strain. Place liquid and fibre in dyepot and add more water if necessary. Bring to a high simmer for 1 hour. Let fibre cool in dye liquor for at least one more hour or overnight then wash and rinse.
Light and washfastness: moderate to good.

Aluminum acetate
May 26/22 - back in stock, finally!
Used as a MORDANT in natural dyeing, which allows the plant pigments to bond with the fibres.
NOT THE SAME AS ALUM!! Aluminum acetate is used as a one-step mordant on cellulose (plant) fibres such as cotton, linen and well worth experimenting with on rayon fibres (including Tencel), bamboo, ramie, hemp and others. This is a more expensive but faster means to get natural dyes to stick without the more traditional alum/tannic acid premordanting method.
TO USE: weigh dry fibre and scour if needed (especially cotton). Calculate mordant required for 5% WOF (weight of fibre). Weigh and dissolve in hot water. Fill pot with sufficient water for the fibre to move, add mordant and stir. Enter fibre. Bring to 190-200°F and hold 1 hour. Stir yarns frequently. Cool overnight, then wash well. Dye immediately or dry for later.
Spent mordant solution may be safely disposed of down the drain (except for septic systems). It also may be diluted and poured on the ground, for instance on a gravel driveway or path.
CAUTION: wear a mask when handling powders. Wear gloves when handling powder or solutions, particularly when rinsing or handling wet yarns. Best done outdoors or with very good ventilation.

Soda ash
Used with fibre reactive dyes as a colour FIXATIVE. Soda ash raises the pH and allows the dye to bond with the fibre. Generally used only with cellulose (plant) fibres such as cotton or flax. Also known as washing soda or sal soda, though this is a more pure form that the washing soda sold in supermarkets.
Also sometimes used in natural dyeing to create more alkaline conditions, and thus altering the colour with certain plants. Extensively used for indigo vat dyeing.
TO USE: Follow dye manufacturer’s directions for amounts and timing.
Dispose of spent dyebath in the usual way, most likely down the drain.
CAUTION: Wear a mask when handling powders. Wear gloves, can be a skin irritant.