‹‹‹ Vitr. 7.13.3 | Table of Contents | Vitr. 7.14.2 ›››
14Purple colours are also made by tinging chalk with madder-root and hysginum. Divers colours are also made from flowers. Thus, when dyers are desirous of imitating the Attic ochre, they put dry violets into a vessel, and boil them. When so prepared, they pour the contents of the vessel on to a cloth, and, squeezing it with their hands, receive in a mortar the water thus coloured by the violet, and then, mixing Eretrian earth with it, and grinding it, the colour of Attic ochre is produced.
14Purple colours are also manufactured by dyeing chalk with madder root and with hysginum. Other colours are made from flowers. Thus, when fresco painters wish to imitate Attic yellow ochre, they put dried violets into a vessel of water, and heat them over a fire; then, when the mixture is ready, they pour it onto a linen cloth, and squeeze it out with the hands, catching the water which is now coloured by the violets, in a mortar. Into this they pour chalk and bray it, obtaining the colour of Attic yellow ochre.