PAINTS, DYES, AND VARNISHES 



eight parts, a very deep shade of Brunswick green is 

 produced. Of course the quality and color of the Prus- 

 sian blue and the chrome yellow have to be taken into 

 consideration, but the general rule holds good in any 

 case. 



As pigments, the Brunswick greens work well either 

 in oil or water. They have good covering power, and 

 as they are permanent enough for all practical purposes, 

 and mix well with most other pigments, they are favorites 

 with practical painters. 



The chrome greens, which are usually mixtures of 

 oxides and phosphates of chromium, are very popular 

 pigments with both artists and artisans, on account of 

 their brilliance of color, permanence, and good mixing 

 qualities. When mixed with other oil pigments they 

 remain unchanged, and have no effect upon the other 

 pigments; but as water-colors they change slightly 

 in time. In the experiments conducted by Messrs G. 

 Rowney & Company, of London, to determine the per- 

 manency of various colors, the specimen of chrome green 

 mixed with flake white and exposed to sunlight for twelve 

 months showed only the slightest change from the 

 original shade. 



There are several copper greens which at various 

 times in the past have been important as pigments, but 

 all of these have gradually ceased to be of importance 

 to the painter. Of these verdigris, Scheele's green, and 

 emerald (or Paris) green, form a group similar in com- 

 position, each one of which has had its period of popu- 

 larity only to be supplanted by another pigment. Verdi- 

 gris, an acetate of copper, is the oldest and poorest 



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