Chemical Composition: ICP-MS/AAA data from sample, Leaded Bronze:
Cu, 66.29; Sn, 7.82; Pb, 25.1; Zn, 0.36; Fe, 0.23; Ni, 0.03; Ag, 0.07; Sb, 0.1; As, less than 0.10; Bi, less than 0.025; Co, less than 0.005; Au, less than 0.01; Cd, less than 0.001
J. Riederer
Technical Observations: The patina of both the bolt (1964.12.13.A) and socket (1964.12.13.B) is green with areas of red, brown, and black. The bolt was fractured at one end prior to burial. 90% of the top of the tapered bolt is a brittle fracture; 10% is a deformation caused by a tool, which may have been used to cause the break. There are two chisel indentations (each 1 cm long) on one face of the bolt; the same tool made marks at the center of all four upper edges of the socket, perhaps to help set it into the floor. All of these marks pre-date corrosion. The c. 15 dents on one side of the bolt post-date the formation of corrosion and may have been caused by an excavation pick.
The bolt and socket were probably cast in clay molds. The socket may have been embedded in a floor to receive the bolt vertically. Red, white, and gray lead residue is present on the socket’s exterior to secure it, and the two bosses would have added mechanical traction.
Henry Lie (submitted 2012)
