7. May, 2020

A simple Test for Iron for Eco dyers/printers

While I haven't been doing much eco printing over lockdown that has had more to do with no mordanted fabric than lack if interest. I am going to mordant some fabric now because i want to begin a record of how the tannin in leaves changes the prints on a month to month basis. It is the intereaction or tannin and iron that provides the clear outlines of leaves. The level of iron in tapwater is an essential to test for to get good eco prints where iron bleed is minimised. Here is a simple test to find out the level of iron in your tapwater. Measure equal amounts of distilled water into one jar and tap water into a second. Label each jar appropriately. Add a small amount of tannin to each jar (about 1/8 - 1/4 teaspoon. Stir well. If you have access to oak gall this will give a pretty clear solution but in NZ we do not have the wasp that makes these galls so I have used Haritaki powder as the tannin source. Hence my liquids are a very pale amber - paler than they look in the photo. Leave the jars for at least 24 hours. If you have a concentration of iron in the tap water this jar will be significantly darker that the control distilled jar. I was happy to find that there was no appreciable difference in my two jars so I will be able to quite happily use tap water in my eco dying work