blue ink

Evidence

"The first five pages (fols 1a-3a), which comprise the introduction to the third volume of the Mas̲navī, are copied in alternating rows of gold and blue tawqīʿ."

Remarks

Blue is used for alternating rows of calligraphy in the introduction (fols 1a-3a). Diacritical marks for the blue text are written in gold (p. 150).