Some manufacturers produce this beautifully rich color. It is very like cobalt, but slightly darker.
To get this shade mix one part of zinc white and chrome green with four parts of ultramarine blue and a touch of black.
This color is certainly the most important blue the painter has. It cannot be imitated. It works well in both water and oil, and is transparent. It is very strong and care must be exercised in using it lest too great a quantity is added to a batch of paint, which might be spoilt in consequence.
Add a little black to Prussian blue, and lighten up with white.
Use white for base, tint with ultramarine until a fairly strong blue is obtained, and then tinge with a little lemon chrome green.
This is made by adding a little white to Prussian blue with a touch of crimson lake. Some manufacturers make -a very rich blue, which they sell under the name of Royal blue.
One part of Chinese blue mixed with double the quantity of oxide of zinc. This should not be used for outside work.
Two parts of Prussian blue, three parts of raw sienna, thirty parts white.
One part of Prussian blue added to one hundred and twenty parts of white lead give a sky blue, but some prefer cobalt, and this is for many purposes doubtless the best. Still another method of obtaining sky blue is to tint white lead with a little lime blue, adding a very little middle chrome, but the latter is more suitable for a distemper color than it is for an oil paint, as lime blue is not very lasting in oil.
Zinc white tinted with lime blue gives this color for distemper.
One part of raw umber, twice the quantity of Prussian blue on a base of white lead will give this color.
Mix together four parts of ultramarine blue and one part of crimson lake. This is suitable only for artists' use.
Two parts of cobalt blue, one part of emerald green, twelve parts of white lead.
This is one of the chief blues used by painters, and must be bought ready made. It cannot be imitated, but it can be bought in many different qualities. It must not be mixed with chromes or white lead, as it contains sulphur.