{"product_id":"iron-mordant-ferrous-sulphate","title":"IRON MORDANT | Ferrous Sulphate","description":"\u003ch1\u003e\u003cspan\u003eIron Mordant – Ferrous Sulphate\u003c\/span\u003e\u003c\/h1\u003e\n\u003cp\u003e\u003cem\u003e\u003cspan\u003eColour Modifier · Mordant \u003c\/span\u003e\u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eIron, or ferrous sulphate, is a powerful natural-dye mordant and colour modifier. It darkens and “saddens” colours, creating olives, greys, browns, charcoals and deeper muted shades.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eYellow dyes may shift towards olive or green, although this depends on the dye plant - some yellows become brown or grey instead. With tannin-rich dyes, iron can produce deep greys and near-blacks.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eIron may improve the lightfastness of some plant dyes, but it cannot make every fugitive colour permanent.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2\u003e\u003cspan\u003eAt a glance\u003c\/span\u003e\u003c\/h2\u003e\n\u003cdiv\u003e\n\u003cdiv\u003e\n\u003cdiv\u003e\n\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003e\u003cspan\u003eFeature\u003c\/span\u003e\u003c\/th\u003e\n\u003cth\u003e\u003cspan\u003eDetails\u003c\/span\u003e\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan\u003eProduct\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan\u003eFerrous sulphate\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan\u003eFunction\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan\u003eMordant and colour modifier\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan\u003eSuggested quantity\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan\u003e1–3% WOF\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan\u003eStarting quantity\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan\u003e1% WOF\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan\u003eSuitable fibres\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan\u003eWool, silk, cotton, linen and other textile fibres\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan\u003eBest application\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan\u003eWarm and added directly to the dye bath near the end\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan\u003eProcessing time\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan\u003eUp to 10 minutes, aerating. Repeat up to 3 times.\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan\u003eColour effects\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan\u003eOlive, green, grey, brown, charcoal and muted shades\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003ch2\u003e\u003cspan\u003eHow much to use\u003c\/span\u003e\u003c\/h2\u003e\n\u003cp\u003e\u003cspan\u003eBegin with:\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003e1g iron per 100g dry fibre\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eEquivalent to \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e1% WOF - weight of dry fibre\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eFor most work, \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e1–3% WOF\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e is sufficient. Begin at 1% and only add another 1% if repeated immersion and aeration have not produced enough change.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eSome colours may not shift noticeably until approximately \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e5% WOF\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, but this concentration presents a much greater risk of fibre damage and is not recommended for routine use.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2\u003e\u003cspan\u003eSuggested method\u003c\/span\u003e\u003c\/h2\u003e\n\u003cp\u003e\u003cspan\u003eIron reacts with oxygen, and much of the final colour develops while the fibre is exposed to air.\u003c\/span\u003e\u003c\/p\u003e\n\u003col start=\"1\"\u003e\n\u003cli\u003e\u003cspan\u003eComplete the main dyeing process.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\n\u003cspan\u003eDissolve \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e1% WOF ferrous sulphate\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e thoroughly in a little warm water.\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eAdd the solution directly to the warm dye bath when finished dyeing.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\n\u003cspan\u003eImmerse the fibre and move it regularly for up to \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e10 minutes\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e.\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eUse a shorter immersion for delicate fibres such as silk.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\n\u003cspan\u003eRemove the fibre and hang it up or spread it out for approximately \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e10 minutes\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, allowing air to reach it evenly.\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eReturn it to the bath and repeat the immersion and aeration cycle if required.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eUp to three cycles are usually sufficient. Further repetitions generally produce little additional change.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\n\u003cspan\u003eIf the colour remains too light after three cycles, dissolve and add another \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e1% WOF iron\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, then repeat the process.\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eRinse thoroughly once the desired shade has developed.\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003cp\u003e\u003cspan\u003eMaintain a little warmth throughout the process. Warm application directly in the dye bath is generally more effective than a cold treatment or separate afterbath.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eWatch the colour during every stage. It may continue to darken considerably while hanging in the air.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2\u003e\u003cspan\u003eMaking ferrous acetate\u003c\/span\u003e\u003c\/h2\u003e\n\u003cp\u003e\u003cspan\u003eWe generally prefer to convert ferrous sulphate into a ferrous acetate working solution.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eUse:\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003e1 part ferrous sulphate\u003c\/span\u003e\u003c\/strong\u003e\u003cbr\u003e\u003cstrong\u003e\u003cspan\u003e1 part sodium acetate\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003col start=\"1\"\u003e\n\u003cli\u003e\u003cspan\u003eWeigh equal quantities of ferrous sulphate and sodium acetate.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eDissolve them in warm water and mix thoroughly.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eAdd the freshly prepared solution directly to the dye bath.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eUse immediately.\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003cp\u003e\u003cspan\u003eFerrous acetate can act more strongly than ferrous sulphate alone. Begin with \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e1% iron\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, calculated from the weight of the ferrous sulphate - not the combined weight of both ingredients.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eFor example, for 100g of fibre, use:\u003c\/span\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cspan\u003e1g ferrous sulphate\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003e1g sodium acetate\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cspan\u003eSodium acetate is sold separately.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2\u003e\u003cspan\u003ePossible colour changes\u003c\/span\u003e\u003c\/h2\u003e\n\u003cdiv\u003e\n\u003cdiv\u003e\n\u003cdiv\u003e\n\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003e\u003cspan\u003eOriginal colour\u003c\/span\u003e\u003c\/th\u003e\n\u003cth\u003e\u003cspan\u003ePossible result with iron\u003c\/span\u003e\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan\u003eYellow\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan\u003eOlive, green, brown or grey\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan\u003eRed or pink\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan\u003eBurgundy, plum, brown or muted purple\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan\u003eTannin-rich beige or brown\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan\u003eGrey, charcoal or near-black\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan\u003eBright botanical colours\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan\u003eDarker, softer or more muted shades\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cp\u003e\u003cspan\u003eResults depend on the dye, fibre, water chemistry and amount of iron used. Always test a sample first.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2\u003e\u003cspan\u003eImportant fibre care\u003c\/span\u003e\u003c\/h2\u003e\n\u003cp\u003e\u003cspan\u003eIron can damage fibres when used excessively or left in contact with them for too long.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eFor most projects, stay within \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e1–3% WOF\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e and build the colour through repeated immersion and aeration rather than immediately increasing the iron concentration.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eUse shorter immersion periods for silk and other delicate materials. Although some colours may only shift at approximately 5% WOF, this higher concentration presents a significantly greater risk of weakening the textile.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eFerrous acetate is preferable when a more controlled, fibre-friendly iron treatment is required.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2\u003e\u003cspan\u003eStorage and safe handling\u003c\/span\u003e\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cspan\u003eStore tightly sealed in a cool, dry place.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eHarmful if swallowed.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eCauses skin and serious eye irritation.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eAvoid creating or breathing dust.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eWear gloves and eye protection while measuring and dissolving.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eWork in a well-ventilated area.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eUse dedicated dyeing utensils - never food-preparation equipment.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eKeep away from food, children and pets.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eDo not discharge concentrated solutions into drains or waterways.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eFollow local guidance when disposing of iron-containing solutions.\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003e\u003cspan\u003eWhat you receive\u003c\/span\u003e\u003c\/h2\u003e\n\u003cp\u003e\u003cspan\u003eYour chosen net weight of ferrous sulphate, supplied in a sealed pouch.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2\u003e\u003cspan\u003eLearn with us\u003c\/span\u003e\u003c\/h2\u003e\n\u003cp\u003e\u003cspan\u003eJoin \u003c\/span\u003e\u003ca href=\"https:\/\/the-natural-dyers-academy.mn.co\/\"\u003e\u003cspan\u003eThe Natural Dyers \u0026amp; Growers Academy\u003c\/span\u003e\u003c\/a\u003e\u003cspan\u003e to share results and explore natural colour alongside fellow dyers and growers.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e","brand":"AppleOak FibreWorks","offers":[{"title":"25g","offer_id":18713869942841,"sku":"greening","price":6.95,"currency_code":"EUR","in_stock":true},{"title":"50g","offer_id":18713869975609,"sku":"greening","price":7.5,"currency_code":"EUR","in_stock":true},{"title":"75g","offer_id":18713870008377,"sku":"greening","price":7.95,"currency_code":"EUR","in_stock":true},{"title":"100g","offer_id":18713870041145,"sku":"greening","price":8.5,"currency_code":"EUR","in_stock":true},{"title":"250g","offer_id":47368925643088,"sku":"greening","price":11.95,"currency_code":"EUR","in_stock":true},{"title":"500g","offer_id":47368925675856,"sku":"greening","price":17.95,"currency_code":"EUR","in_stock":true},{"title":"1kg","offer_id":47368925708624,"sku":"greening","price":29.5,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0098\/2918\/7641\/files\/Iron_sulphate.jpg?v=1794228723","url":"https:\/\/appleoakfibreworks.com\/products\/iron-mordant-ferrous-sulphate","provider":"AppleOak FibreWorks","version":"1.0","type":"link"}