As a plant dyer, I am very interested in the mordanting process which can help the dye material better attach to the yarn fibres. However, there are many options available so which one should I use? I decided to carry out an experiment to determine how a range of possible mordants might affect the resulting colour, here in my dye studio in Edinburgh using Scottish water!
I scoured five 25g mini skeins of Jamieson’s of Shetland undyed natural white Shetland wool and set one aside as a control. Next, I mordanted the other four skeins as follows:
- alder cone solution heated to 60°C then simmered for 1hr then left overnight. The alder cone solution was made by simmering 100%WoF i.e. 25g of cones at 70°C in 2l of water for 1hr then left overnight then strained;
- Symplocos solution heated to 60°C then simmered for 1hr then left overnight. The solution was made by simmering 20%WoF of Symplocos powder at 60°C in 4l of water for 1hr then left overnight then strained;
- 20%WoF of aluminium triformate in 4l of initially warm water for 24hrs; and
- 20%WoF of alum (aluminium potassium sulphate) in 4l of water heated to 60°C then simmered for 1hr then left overnight.
I chose to use some dried marigold flowerheads from Bailiwick Blue as my dye material. The weight of these was 99g. The dry weight of the now mordanted plus the control yarns came to 124g. Hence the dye would be at a ratio of 80%WoF.
To create the dye, I simmered the flowerheads in 5l of water at 60°C for 1hr then allowed to cool. The flowerheads were then strained off and the now overnight soaked yarns added to the dye pot. The pot was then heated and simmered for 1hr at 60°C. The pot was then switched off and allowed to cool. The yarns were removed and dried slowly overnight.
The results as shown below are fascinating. I didn’t expect the alum and the aluminium triformate to be quite so different!
Of course, there are other very important variables to take into account when choosing a mordant:
- The provenance of the mordant;
- The manufacturing processes;
- The transporting to Edinburgh;
- The energy efficiency of the mordanting/dyeing processes; and
- The cost
And the conclusion? Well, for myself I will continue to use alum bought from George Weil and manufactured here in the UK. And my next experiment needs to look at the various alum mordanting methods I can use!