Chemical Composition: Main
XRF data from Tracer
Alloy: Bronze
Alloying Elements: copper, tin
Other Elements: lead, iron
Corroded area
XRF data from Artax 1
Alloy: Bronze
Alloying Elements: copper, tin
Other Elements: lead, iron, arsenic
K. Eremin, January 2014
Chemical Composition: SEM-WDS data from sample, Bronze:
Cu, 94.7; Sn, 5.0; Pb, nd; Zn, nd; Fe, 0.08; Ni, nd; Ag, nd; Sb, nd; As, 0.17; Co, nd
Comments: Highly corroded; only small islands of metal remain.
R. Newman, June 2015
Technical Observations: The disc was shaped from sheet metal, which was hammered and then raised by repoussé to form the decorative elements in the center and along some of the edges. Much of the disc is missing, probably as a result of mineralization, which must have weakened the metal in select areas. The two sets of paired holes along the remaining edge were made by punching through the metal; their edges are raised on both the front and back. The original surface of the object would have been smooth and finished. Much of the surface now appears to have a fine, even darker layer that delaminates easily in some areas, exposing a smooth reddish-brown metallic surface. The back of the delaminating layer is slightly greener. Much of the surface is also distorted by large green malachite formations.
Francesca G. Bewer (submitted 2012)