Mordanting

What is Mordanting

Mordanting is the first step of the natural process. It allows the natural dyes to stick to the textile fibres better. Resulting in more durable and long-lasting colours.
This booklet will focus on Alum (potassium aluminium sulphate) mordant as this is the mordant that works best with protein fibres like wool.

Other types of mordant chemicals work best with different types of fibres the most distinct difference being cellulose and protein fibres.
Cellulose fibres (hemp, linen, cotton) have a straight structure where as protein fibres (wool, silk) have a spring like structure. This structure makes protein fibres best at bonding with natural dyes producing more vibrant colours, particularly when a mordant is used.