The exigencies of printing allow us in our reproduction of the pigment colors to give only approximate values. This is no disadvantage to the reader, who must test the colors and mixtures for himself if he is to profit at all from these studies. The comparison of the real paints with
the illustrations in this book will be an excellent test of the value of his purchases.
The following list shows which colors are needed for the first practical essays, while those entered in italics are desirable but not essential. The smallest pans of watercolor, but of first-class quality, are sufficient. Very little will be used, so that they will form the basis of a watercolor box for later work.
You will also need a sheet of best, smooth watercolor paper and at least one fairly large sable brush about size 16, with a worn point, since only broad strokes will be made.
Once again let us insist: there is no sense in beginning with second-rate paints and paper.
BLUE: Ultramarine fine ground/Prussian or Paris blue (iron cyanogen )/Cobalt blue deep, light/Cerulean blue.
YELLOW: Ochre Golden ochre/Mars yellow/Cadmium yellow light, medium and dark/Naples yellow (lead antimoniate), light and dark.
RED: Mars red/Cadmium red dark, light/Alizarin red/Venetian red (iron oxide/ Pozzuoli red.
GREEN: Viridian (hydrous green chromic oxide/Chrome green, (Anhydrous green chromic oxide) /Terre verte (ferrous oxide and silicic acid) /Emerald green.
BLACK AND WHITE: Ivory black/Lamp black/White lead/Zinc white.
There are less varied tones of the different pigments in watercolors than in oil or dry powder colors.
BLUE is found in nature in only two forms: mountain blue, a compound of copper which is impermanent, and lapis lazuli, a blue semiprecious stone. Neither raw material is used today for making colors, although lapis lazuli is unaffected by light. It was used in old paintings as a costly glaze over modeled underpainting, and the stone was thus sometimes called glaze stone. The name ultramarine has also remained current, since it was brought from overseas, beyond the Caspian.
ULTRAMARINE BLUE is now made artificially from a combination of soda, alumina, sulphur, and silicic acid, and is an essential blue pigment for both art and commercial paints, being inexpensive to produce.
(There are also ultramarine red and violet, but they are unimportant.) Ultramarine blue is the nearest of all pigments used to primary blue in the color circle. It has high tinting strength and is very pure. It can be mixed with green or red and gives the purest of mixed violets when combined with alizarin red. It gives only dull greens when mixed with yellow pigments, but it gives a pure blue-green with viridian. Since it has been made to resist lime, it has become the most important blue for murals and house painting. Even in the humblest school child's paint box it is found in a fairly pure form.