Madder Root is the best natural pink-red botanical dye to use for soap and fabrics. The depth and strength of red will vary from palest pink, to rosy pink to a deep earthy red depending on the amount used. The powdered root is the easiest to use in soap because you will achieve consistent results.
This root has been used for as a dye for at least 3000 years. The earliest example of madder dyed linen was found in Tutankhamen's Tomb (from 1350 BC), and it is considered to have been used in prehistory. Popular with the Vikings, and during the Middle Ages, it was in the 19th Century madder was finally made into a longer lasting pigment which we know as "Madder Lake" (the dyestuff is known as Alizarin)
According to Culpepper's herbal, the plant is ruled by Mars and has an opening quality, and will bind and strengthen afterwards........ interesting eh? But back to soaping!!
If using directly into traced soap, we suggest starting with 2 rounded teaspoons per 2kg of oil weight. Either moisten with some Olive Oil, or add directly to the traced soap. This will give you soap as the paler coloured soap with the pattern shows (1/2 teaspoon of Madder Root Powder in oil, added to 250g of traced Cold Process soap). If you wish to avoid the specks and go for the darker look, double or triple infuse into oil first, and then use as a part of the oil portion.
You can also infuse Madder powder for use in lip balm.