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Tannin Blend
$5.83 – $23.85
This is a blend of NATURALLY-SOURCED Tannin, usually from Quebracho and Sumac, possibly others. It will leave your plant fibres or fabrics a soft red-brown base colour before using other dyes.
Used mainly on as a MORDANT on cellulose fibres such as cotton, usually in combination with Alum.
TO USE: weigh dry fibre. Calculate mordant required at 15 to 20%% WOF (weight of fibre) each of Tannic Acid and Alum. Weigh mordants and dissolve in hot water in separate plastic or non-reactive containers. Add wetted fibre to Alum solution and soak for 12 to 24 hours. Rinse and place in Tannic Acid solution for 12 to 24 hours. Rinse again and place back in Alum solution for 12 to 24 hours. Wash and rinse well, then dye or dry for later use.
Spent mordant solution may be safely disposed of down the drain (except for septic systems). It also may be poured around garden plants that prefer acidic soil conditions.
CAUTION: wear a mask when handling powders. Wear gloves when using tannins, particularly when rinsing or handling wet yarns as they can cause skin irritation and staining.
Related products
Oxalic acid
Used occasionally as an ASSIST in natural dyeing. Oxalic acid will alter the shades of cochineal dyebaths, pushing them towards brilliant orange-red.
Also used to help absorption of Tin when premordanting. Dissolve with the tin in hot water at 2% WOF then add to premordanting water, mix and enter fibre.
TO USE: with cochineal baths, use at 2% WOF (weight of fibre). Dissolve first in hot water then mix into dyebath before entering fibre.
Dispose of spent dyebath on the ground.
CAUTION: POISON!!! Wear a mask when handling powders, absolutely wear gloves at every stage with Oxalic acid. MUST BE DONE OUTDOORS: fumes can be an extreme irritant.
Copper sulphate
Used as a MORDANT in natural dyeing, which allows the plant pigments to bond with the fibres.
Copper tends to take the dyed yarn colours towards the brown and green ends of the spectrum. A natural dye that comes out bright yellow with an Alum mordant will look very different with copper.
Used mainly on protein fibres such as wool, alpaca, silk. Although we love to use copper as a premordant, many dyers simply use it after dyeing to push the colours a different direction. To do this, add only 25% by weight of the usual premordanting amounts. Dissolve in hot water. Remove fibre from the dyebath, stir in the copper solution, re-enter the fibre and heat for another 15 minutes. Cool and rinse as usual.
TO USE: weigh the dry fibre. Calculate mordant required for 2% WOF (weight of fibre) and white vinegar at 40ml per 100g fibre. Weigh copper and dissolve in hot water. Fill pot with sufficient water for the fibre to move, add copper, vinegar and stir. Enter fibre. Bring to 180-200 deg F and hold 1 hour. Stir yarns frequently. Cool overnight, then wash well. Dye fibre immediately or dry for later use. These directions that include vinegar are recommended by Jenny Dean in her various natural dye books. Older recipes tend to use 8% copper sulphate all by itself, as a premordant.
Spent mordant solution is best disposed of on the ground, such as a gravel driveway. Keep well away from tree roots and anywhere that may drain to a pond or water feature, since copper sulphate is toxic to plants, fish and other aquatic life.
CAUTION: wear a mask when handling powders. Wear gloves when using copper, particularly when rinsing or handling wet yarns as can be absorbed by the skin. BEST DONE OUTDOORS or with very good ventilation. Avoid breathing fumes.
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.
Iron sulphate
Used as a MORDANT in natural dyeing, which allows the plant pigments to bond with the fibres.
Iron darkens or "saddens" colours. It takes only a tiny amount to do this, and one must be careful with iron: too much will harshen or damage fibres. If you use iron with any regularity, consider having a dedicated pot for this purpose, as it sticks to pot surfaces and will affect the colour of future dyebaths. A chipped enamal pot is perfect.
Used mainly on protein fibres such as wool, alpaca, silk. Although it can be used as a premordant, most natural dyers use iron to alter the colour at the end of the dyeing process. If you prefer to premordant, follow the usual steps using iron at 6% WOF.
TO USE: Weigh fibre before wetting. Dye in the bath of your choice, with or without an alum premordant. Calculate iron mordant required for 2% WOF (weight of fibre). Dissolve iron in hot water. Remove fibre from warm dyepot, stir in dissolved iron and re-enter fibre. Simmer for 5 minutes, cool then wash and rinse well.
Spent mordant solution may be safely disposed of by pouring in the garden. Iron sulphate is a common soil amendment in agriculture and horticulture.
CAUTION: wear a mask when handling powders. Wear gloves when using iron, as it stains skin easily. BEST DONE OUTDOORS or with very good ventilation. Avoid breathing fumes.
