Minerals and Metals in Ancient India v1.c28.s8.t5.17

v1.c28.s8.t5.17

Lead is a low melting point metal insoluble in copper. Up to 2 per cent lead in molten copper improves fluidity and thus it clearly aids in casting. At higher percentages the globules form ‘lakes’ of lead and the lead-copper/bronze interface causes weakness and cracking if hammered. Most Tibetan images contain only moderate quantities of lead which is at variance from some of the Kashmir and North Indian examples. Cleveland Buddha (sample No. 1) contains 11.0 per cent lead. The brass statue of Sūrya from Kashmir (Lee, 1967) contains 2.75 per cent lead, 18.7 per cent zinc and 78.1 per cent copper. Uhlig (1979: 122) has described a brass Buddha containing 10. 37 per cent lead, 13.2 per cent zinc and 73.1 per cent copper. The Newar sculptors preferred far less quantities of lead which are soluable in mercury and thus hinder the process of gilding using mercury. It is noteworthy that many fire-gilded brass statues and copper icons contain negligible quantitites of lead (*vide* Nos. 5, 8, 10-13 in Table 20.9).