Pitt Artist Pen Brush India ink pen
ultramarine
light indigo
Polychromos colour pencil
151 helioblue reddish
145 light phthalo blue
Albrecht Dürer watercolour pencil
cobalt blue
skyblue
helioblue reddish
light phthalo blue
dark indigo
ice blue
phthalo blue
Colour Grip colour pencil
Pastel blue
Sky blue
Midnight blue
120 ultramarine
146 skyblue
157 dark indigo
110 phthalo blue
140 light ultramarine
152 middle phthalo blue
247 indanthrene blue
246 Prussian blue