On the origins of niello

This paper presents a study on the earliest examples of niello scientifically identified up to now. Niello is a black material consisting of one or more metal sulfides that can be used as decorative filling in keyings or channels cut on metals. On the origins of niello there exists quite a few misunderstandings and confusion, because in the past all black materials on metals were called “niello” without any discrimination between different substances and techniques. For instance, formerly it was believed that niello was employed in Egypt and in the Mycenaean world in the mid 2nd millennium BC, however various studies in the nineties of the last century demonstrated that the earlier black inlays on metal objects are not metal sulfides, but copper-based, artificially black patinated alloys. After the identification of the black patinated alloys it was then supposed that niello had been invented by the Romans, because it seemed that the earliest instances of decorative black sulfides on metal appeared in the 1st century CE. However, at the end of the nineties of the last century, three different instances of niello were identified on Late Classical and Early Hellenistic objects. In the meantime, more examples of early niello have been discovered and confirm the existence of this material in the 5th-4th century BC. The method employed for the identification of niello on the various objects has been X-ray Diffraction (XRD) in most cases. In some cases, when sampling was not allowed, non-destructive methods such as Energy Dispersive Spectrometry in the Scanning Electron Microscope (SEM-EDS) was employed when the objects were small enough to be put into the SEM chamber. When the objects were larger X-ray fluorescence spectrometry (XRF) was used. In some other instances, only an autoptic examination of some pieces was sufficient to establish if a black material had been applied on specific objects or not. This paper discusses the new discoveries and discusses the possible area of origin of this decorative material.