Chemical Composition: ICP-MS/AAA data from sample, Mixed Copper Alloy:
Cu, 71.63; Sn, 8.24; Pb, 10.16; Zn, 9.2; Fe, 0.56; Ni, 0.04; Ag, 0.08; Sb, 0.08; As, less than 0.10; Bi, less than 0.025; Co, less than 0.005; Au, less than 0.01; Cd, 0.011
Chemical Composition: XRF data from Tracer
Alloy: Mixed Copper Alloy
Alloying Elements: copper, tin, lead, zinc
Other Elements: iron, silver, antimony
K. Eremin, January 2014
Technical Observations: The patina of 1920.44.219 is dark green, and the surface is well preserved. The corrosion products are a preserved matte texture, which does not appear to have been scraped down.
Because of their heavy weight, the rings (1895.202.A, 1895.202.C, 1920.44.219, and 1977.216.2123.13) appear to have been cast. However, there is no physical evidence of casting. All of these rings are at least slightly non-circular, especially 1977.216.2123.13 and 1895.202.C, the two heavier rings. The gentle ridges on these four rings are carefully planned as subtle decorative elements, each ring with a slightly different profile of facets. The ridges, although smooth, show slight irregularities. These seem more consistent with finishing the wax or pre-wax model by turning rather than cutting the metal ring with a turning process.
Henry Lie (submitted 2002)