Abstract: Monoazo chromiferous dyestuff of the formula: ##STR1## in which A represents phenylene which is unsubstituted or monosubstituted by nitro, chloro or sulpho, or disubstituted by nitro and sulpho or chloro and sulpho or methyl and nitro or chloro and chloro, B represents 1-phenyl-3-methyl-5-pyrazolyl monosubstituted on the phenyl by sulpho, chloro or ethyl, ethylidene acetanilide, hydroxyquinolidene, hydroxyphenylene, naphthylene substituted by one sulpho or one methyl, one of A or B is substituted by sulpho, Y.sub.1 represents --O-- or ##STR2## Y.sub.2 represents --O-- or ##STR3## Y.sub.1 and Y.sub.2 are each in a vicinal position with respect to azo, and Z is water, ammonia and pyridine.

Abstract: Monoazo chromiferous dyestuffs of the formula: ##STR1## in which A and B each represent a naphthalenic nucleus, one of the residues A and B carrying a sulphonic acid group, Y.sub.1 represents --O-- or ##STR2## Y.sub.2 represents --O-- or ##STR3## and Y.sub.1 and Y.sub.2 are each in a vicinal position with respect to the azo group, D is the residue of a .beta.-diketone bidentate chelating agent and Z represents water, ammonia or pyridine, and process for the preparation of such dyestuffs.