hematite

Ingredients

hematite, gum, stone, earth

Preparation Steps

Original Recipe Text

Known as Koya, it is written using red vowels. It is made from a sort of stone rubbed down or a certain type of earth (p. 14). Koya is a processed red earth (iron oxide red or red ochre) kneaded into gum (p. 14). Red ochres contain hematite and are ground and sieved into pigments; through levigation (wet grinding) and decantation, these minerals can be homogenized into finer products (p. 10-11).

Evidence

"In red particulate inks, hematite, the colorant in iron oxide red, was identified by its microscopic appearance... More than three dozen samples with red particulates were tested with hydriodic acid. None were soluble, confirming iron oxide red or hematite. XRF (X-ray fluorescence) spectroscopy (Thermo Scientific Niton XL3t) on the same two folios confirmed the identification of iron in the red inks."

Remarks

The quality of red ochre Koya ink was directly dependent on the effort and repetition in pulverization, levigation, and decantation. It could be coarse or fine enough for 1mm nib reed pens (p. 18). Red pigments also included organic leaf extracts like karan dafii from guinea corn (p. 18).