Use the table to work out which binder to use. If you are using a new pigment, try making a small quantity of test pastels first. If the binder is too strong they will be too hard. To avoid wasting the materials, grind them up in a pestle and mortar, add the same quantity of pigment and mix with water. Conversely, if they are too soft, grind them and mix them with binder.

Pigment	Binder
Base (chalk, kaolin etc)	Medium
Whites (titanium, zinc)	Medium
Yellow ochre	Weak
Burnt Sienna	Medium
Burnt Umber	Water
Cadmiums (red, yellow)	Medium
Alizarin crimson	Strong
Pthalo green	Weak
Oxide of chromium	Medium
Prussian blue	Medium
Ultramarine blue	Medium
Lake colours	Weak