mixing gouache primaries

In Reggie Ezell’s year long calligraphic workshop, an assignment was to make a color chart from mixing red, yellow and blue Windsor Newton gouaches.  The hand stamp is from Karv’d, and I carved the inkwell and pen.  It’s a flag book with Hahnemühle Schiller paper measuring 8 ¼ x 4 x ¼” and opening to 17”.   $75.