stylistic:style_transfer, stylistic:tone, structural:expansion, linguistic:paraphrasing
Inks and dyes

Walnut husks can be used to make durable ink for writing and drawing. It is thought to have been used by artists including Leonardo da Vinci and Rembrandt.

Walnut husk pigments are used as a brown dye for fabric and were used in classical Rome and medieval Europe for dyeing hair.