Blue paper

This effect is created through the use of light and dark drawing materials, like chalk, charcoal, ink, and white heightening, on blue paper.

The pulp was removed with sieves and placed as a freshly laid sheet on a felt base in the first drying process (couching).

Further, neither woad nor indigo, the most common blue colorants, require a mordant or substance to fix the dye and were dark enough to cover stains.

[7] The blue color provided a unique starting point for modeling light and shadow compared to the white paper.

This is because the artist usually began with a dark drawing instrument, such as a pen or brush dipped in ink, charcoal, or chalk.

[10] North of the Alps, blue paper was used for drawings from the early 16th century: First by Albrecht Dürer, then demonstrably by Hans Burgkmair and Jörg Breu.

[13] For pastel painting, which emerged in the late 17th century, blue paper was used particularly frequently as a support material alongside parchment, silk, canvas, wood, and copper.