OCHRE: Finlay travels to Arnhem Land and the Tiwi Islands in northern Australia to see 'the first colour paint'. Aboriginal painters have used the red, brown and yellow iron oxides for painting caves, bodies and canvases for thousands of years.
BLACK AND BROWN: Charcoal, still an artists' mainstay, is evident in the neolithic cave paintings of Spain and France. The fine modern Coates charcoal was created in the 1950s when Percy Coates saved his near-bankrupt wicker-basket company by burning the willow stems. Pencil lead (really graphite) first came from England's Lake District in the 16th century. Black ink was used in Egypt and China 4,000 years ago.
WHITE: Lead white - the whitest white and also potentially fatal - shines in Dutch still-lifes and has turned black in cave paintings in Dunhuang, China. Finlay also visits Ubud on the Indonesian island of Bali, where artists prime their canvases with rice powder.
RED: In Santiago, Chile, Finlay finds the cochineal bugs that thrive on prickly pear before their blood is turned into Colour Index No 4 - the bright but unstable cochineal or carmine red loved by the Incas and still used in dyes, make-up and food colouring.
ORANGE: The mystery of the orange varnish used on violins takes Finlay to Cremona in northern Italy. In Turkey she digs for madder root, an ancient source of orange and red that created the red bandanna fad of the 1790s. English company Winsor & Newton still makes pink paint from madder.
YELLOW: In a Hong Kong art shop, Finlay finds gamboge, a resin that turns yellow in water, from the landmine-dotted forests of Cambodia. Looking for saffron, she turns from the diminishing crocus crops of Spain to Iran, where a 1,000km journey leads to the centre of modern saffron production.