WAX COATINGS ON ETHNOGRAPHIC METAL OBJECTS: JUSTIFICATIONS FOR ALLOWING A TRADITION TO WANE
DANAL L. MOFFETT
The literature on the conservation of metal objects focuses primarily on archaeological material and decorative arts collections. Consequently, ethnographic conservators must form treatment protocols by extrapolating information from this literature and from more general publications on conservation. Recommendations within these sources are rarely accompanied by warnings of the potential for interfering with the remnant casting material, indigenous coatings, or aesthetic aspects associated with ethnographic objects.
Since the era of Plenderleith, the use of protective wax coatings on metal objects has been advocated widely with several objectives in mind: to produce a barrier that excludes moisture and oxygen from the metal surface, to ensure against further introduction of contaminating elements by handling, and to provide a protective layer for undercoatings, such as Incralac formulated with benzotriazole, which may inhibit corrosion (Plenderleith and Werner 1971; Lafontaine 1981; CCI 1988; Pearson 1988; Barclay 1989; Grossbard 1992). In order to render a more homogeneous appearance on a metal surface, both clear and pigmented wax have been applied ostensibly to enhance objects aesthetically (Organ 1970). The majority of these authors recommend the use of wax blends (e.g., microcrystalline and polyethylene waxes) either made commercially or prepared in the conservation laboratory. Using a case study of a copper alloy Benin commemorative head, this paper will show that wax applications can create unforeseen problems when attempts at removal are made.