This specification covers ferrous earthy pigment included under the general term “ochre.” The pigment shall be a hydrated oxide of iron permeating a siliceous base and shall be free from added impurities and added coloring matter. The following test methods shall be conducted: chemical analysis of dry pigment; coarse particles; mass color and tinting strength; volatile matter; and moisture. The results of these test methods should conform to the pigment requirements.

1.1 This specification covers ferrous earthy pigment included under the general term “ochre.” The pigment may be purchased in the dry form.