Abstract: A process for the production of a compound of the formula: ##STR1## in pigmentary form having a mean particle size not exceeding 0.3 microns, comprising:(a) reacting .beta.-naphthol with chloroform in an alkaline medium, using a sufficiently slow rate of addition of chloroform that the reaction mixture, after initially assuming a deep blue color and then turning green, maintains this green coloration until the addition of chloroform has been completed;(b) reacting the alkali metal salt of 2-hydroxy-1-naphthaldehyde from step (a) with 2-aminophenol to produce a ligand of formula: ##STR2## (c) metallizing the ligand of formula II with an aqueous solution of a coppering agent, and isolating the complex metal pigment of formula I.