March 08, 2022 4 min read

Natural Dye Glossary

We have created a Natural Dye Glossary to help explain some of the terms used in the natural dyeing world. This is not a full list by any means just the ones we thought pop up the most.

Acid - The acidity of a liquid is measured with the pH scale. A pH lower than 7 is defined as an acid. pH is measured with a paper based Litmus Test.

Alkaline - The alkalinity ofa liquid is measured with the pH scale. A pH of higher than 7 is defined as an alkaline. pH is measured with a paper based Litmus Test.

Cellulose fibres - Plant based fibres such as e.g. cotton, linen, hemp, bamboo etc

Colour shifting - How to change the colour of a dye by changing the pH

Crocking - The rubbing off of indigo or dye onto hands or clothes

Dye extract - A concentrated, powdered natural dye. The natural colour has been extracted from the raw material, purified, strained, dried and powdered.

Eco Dyeing - A newer more modern term for natural dyeing with sustainable resources and processes. Dyeing protein and cellulose fibres with natural dyes.

Eco printing - This is the process of dyeing directly on to prepared fabric using dyestuff and leaves, flowers etc. This is rolled into a bundle to enable the dye and leaves to print onto the surface of the fabric when heat is applied.

Fugitive - This term refers to dyestuffs or dyed fibre that lose colour quickly when exposed to light, air, or water.

Lightfastness: The resistance of colour to fading from direct or indirect light exposure

Litmus test: A litmus test is performed using specialist paper to assess the acidity or alkalinity of a liquid. Normally the result is red or blue. Red paper turns blue when the pH is alkaline, while blue paper turns red when the pH turns acidic.

Mordanting: Mordanting is a process to prepare the fibre to bond with natural dyes. Most natural dyes require the use of a mordant to achieve the most durable and long-lasting colours.

Natural Dyes: Ancient dyes such as Madder, Weld, and Cochineal, to name a few, in their natural form as well as extract. 

Natural Dyeing Clothes: Need to know if the clothes are made from Protein or Cellulose fibres as the natural dyeing processes are different.

Natural Dyeing Cotton: Cotton is a Cellulose fibre and the natural dyeing processes must be appropriate for these fibres.

Natural Dyeing Fabrics: Need to know if the fabrics are made from Protein or Cellulose fibres as the natural dyeing processes are different.

Natural Dyeing Plants: Botanical plants that can produce natural dyes.

Natural Dyeing Wool: Natural dyes used to dye Protein Fibres, such as sheep wool, alpaca, silk etc.

pH: The pH scale measures the acidity or alkalinity of water-soluble substances.  The pH scale is 1 to 14, 1 being the most acidic and 14 being the most alkaline. A pH of 7 is neutral and neither acidic or alkaline, (water has a pH value of 7).  This is an easy measuring tool to change the pH in the dye bath which allows a wider spectrum of colours or shades from certain extracts when acidity or alkalinity is altered.

Protein fibre - Anima; based fibres, such as sheep wool, cashmere, mohair, alpaca, and silk.

Scour: A textile term for washing or cleaning fibres prior to mordanting and dyeing.

Tannins: are used in the mordanting of cellulose fibres as they make a bridge between fibre and extract. Some can be used as a dye to add lovely colour to fibre.

Washfastness: The ability of dyed fibres to washout or fade when washed.

Weight of Fibre: The dry weight of the fibre you are going to dye. The process of calculating the correct weight of fibre is not straightforward!

Wetting or wetted out: Before each process you should soak your fibres in plain water. This enables even uptake of dye or mordant.

Natural Dyeing Workshops

Learn how to hand dye protein fibres (animal fibres such as sheep wool, alpaca, yak and silk) or cellulose fibres (plant fibres such as cotton, linen, hemp and bamboo) using the traditional natural dyes. The craft courses are a hands on learning experience using ancient dyes such as Madder, Weld, and Cochineal, to name a few, in their natural form as well as extract. 

Craft Courses for beginners and those with some experience

Located in the north Pembrokeshire countryside, our hands-on craft courses are held in a purpose designed Dye Studio. These courses are suitable for complete beginners and those that have a little experience. They are the foundation blocks of good practice for you to build and develop your own natural dye journey.

Experienced Tutor

All the yarn and scarves for sale on this website have been hand dyed with natural dyes by the Tutor of these craft courses - Hand Dyed Yarn  - Hand Dyed Scarves. See Feature in The Knitter magazine on hand dyeing in the FelinFach Dye Studio - Click here...

About FelinFach

Our company, FelinFach Natural Textiles is located in the heart of the Preseli area of Pembrokeshire near to Boncath. We design Welsh blankets and the iconic Welsh Tapestry blankets which are traditionally woven at Welsh mills. We also design and make natural hand dyed yarn, cotton, silk and wool scarves and other handmade products, all available in our yarn store and shop. We also offer Welsh tartans, Sheepskin Rugs, Gift Cards and tools and books for crafters and knitters - Cocoknits, Laine, Amirisu and Making to name a few! Lastly, craft courses on hand dyeing with 100% natural dyes in the purpose designed FelinFach Dye Studio. We are a proud supporter of the Campaign for Wool, All Things Wales and Global Welsh.

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Last update 19th March 2022