Niello-work (i.e. Black work, from Latin Nigellum) is the technical term for a method of ornamenting metal plates in imitation of pencil drawing, by engraving the surface, and rubbing in a black or colored composition, so as to fill up the incised lines, and give effect to the intaglio picture. It is not quite certain when this art was originated; Byzantine works of the 12th century still exist to attest its early employment. This art must have been known at quite an early date in Christian culture. The monk Theophilus speaks of it, and the patriarch Nicephorus of Constantinople sent, in 811, to pope Leo two jewels adorned with niello. Marseilles was eminent in this art during the reigns of Clovis II and Dagobert. As an art it is claimed to have been brought to high perfection at Florence; and was practiced by Benvenuto Cellini. The finest works of this kind belong probably to the first half of the 15th century, when remarkable excellence in drawing and grouping minute figures in these metal pictures was attained by Maso di Finiguerra, an eminent painter, and student of Ghiberti and Massacio. In the hands of this artist it gave rise to copper-plate engraving, and hence much interest attaches to the art of niello-cutting. Genuine specimens of this art are rare, some of those by Finiguerra are very beautiful and effective, the black pigment in the lines giving a pleasing effect to the surface of the metal, which is usually silver. Those of his works best known are some elaborately beautiful pattines wrought by him for the church of San Giovanni at Florence, one of which is in the Uffizia, and some are in various private collections. In the collection of Ornamental Art at South Kensington there are no less than seventeen specimens of niello-work. See Walcott, Sacred Archeology, s.v.; Elmes, Dict. of the Fine Arts, s.v.