Egyptian goldsmiths were masters of gold construction and were accomplished at utilizing several materials in the manufacturing process.
For very small joins, evidence suggests that malachite was ground and mixed with a natural glue and then placed between the parts to be joined. After the mixture dried and the object was heated, the copper of the malachite diffused into the gold-silver alloy and lowered the melting temperature of the alloy’s surface. Continued heating melted the surface and created a bond at the points of contact (Aldred 1971: 97—100; Ogden 1982: 64f). Figure 90b shows an example of fusion where it is assumed that a copper salt was present (Tutankhamun vulture applique. Carter 256rrrr, Carter 1927: pi. 76d); the gold substrate to which a gold loop was attached had just changed to a melted state. Examples with granules are well illustrated by Baines (1998: fig. 17.3a—c).
In some cases, the joining material is more evident, as on a bangle from the Ahhotep group (Vernier 1907-09: CG 52074), the Wady Qurud rosette retrieved by Chaban (Fig. 89a), on horseshoe rosettes of I14, a box spacer from lion armlet 138 (Fig. 89c), and barrel spacers from the same reconstructed armlet (Fig. 89d). Solder and messy joining is also found in excavated jewels. One of Tutankhamun’s falcon collars shows such a repair at the top row of beads (Fig. 90c [right]; Carter 256gg, SR 313). This collar also shows a reinforcement at the base of the falcon’s neck. Among the catalogued objects below, such reinforcements are quite messy on earring no (Fig. 89b) and the head plate of 114, but neater on medium-quality vulture 28, sandal sole 34, post of gazelle diadem 108 and right ear of proper left gazelle, and tube pendants 180 and 183. East Mediterranean metalwork also shows such reinforcements (see Lilyquist 1993b: fig. 23d). All of these joins are thought to have been made with a powdered copper salt.
Not reported in the literature, however, is the use of square - or sliver-shaped coupons in the initial construction of an object for instances where a copper salt would not have been sufficient to secure a bond (cf. Ogden 1992: 5 if; Oddy 1996: 191). Such coupons can be seen clearly on the high quality hinged ornaments 141 (Fig. 8qe). According to Stone, this is hard solder, sometimes termed brazing alloy in the UK and in industrial technology within the US.
In the diffusion process, the silver-to-gold ratio will inevitably be the same in the join as in the adjacent metal, and copper will have been added to lower the melting point at the join (Stone; see Appendix 2, 108, 133, 138, 141, where two-to-three times as much copper occurs). In the fillet of a hard soldered join, the silver-to-gold ratio usually has no necessary compositional relationship to the substrate material. Most often in modern gold work, the solder will have a karat less gold than the gold of the substrate.
It is sometimes difficult to visually determine whether the solder on purchased gold work is ancient or modem (see also Maryon 1941: 122—4; see pp. 274—7 for solder on modern objects). To the author’s knowledge, there is no published systematic study of joining, and the archaeologist is sometimes left in limbo, especially when lacking analyses (cf. Schorsch 1995: 133).
World History
