Mordant Recipes

Mordants are the chemical compounds used to bind the dye to the fiber. There are some fibers which need almost no mordanting and some dyes will produce strong colors without using mordants at all but these are exceptions rather than the rule.

Alum Mordant Recipe

Alum is the most common mordant used throughout history. It was available from the local apothecary along with orpiment (arsenic) and gum arabic. Gum arabic may have only been used to add weight to the fabric. This was especially important as silk was traded and priced according to its weight.

Copper Mordant Recipe

Green vitrol and copperas are the common names for ferrous sulfate. Blue vitrol and verdigras are the common name for copper sulfate. Many older dye recipes called for the fiber to be boiled for a period in either a copper or iron cauldron. This process would leach out the metal into the fiber. By the end of the 16th century, as chemical additives became available on the common market, the practice of leaching from a metal pot was replaced almost totally by using the chemical compound in a bath. These processes gave much more predictable results and better saturation. This was handled two ways; either by adding the mordant to the dyebath or by preparing a separate mordant bath before the actual dyebath.

Iron Mordant Recipe

Tannic Acid was used often with iron either in the compound form or metal scrapings. When boiled, the tannins and the iron give very dark shades. Vinegar and various salts were used to enhance this process and "to level the bath". Tannins are naturally occurring in many plants; alder bark, oak galls and late summer blackberry leaves are especially rich in tannin.

	Note:
	The recipes provided are quite easy use. I prefer to work using metric units, as this makes cutting down and expanding recipes very easy. The one draw back is finding a scale that will measure as fine as 0.1 gm. But the convenience of easy math makes it worth the effort.