Minerals and Metals in Ancient India v1.c28.s8.t1.2

v1.c28.s8.t1.2

Rosdi in Central Gujarat is a Harappan site which produced mostly copper artefacts significantly contaminated with lead and zinc as impurities suggesting that the ore came from the Zn/Pb bearing Southern Aravalli area. Tin was deliberately added specially in the ring to assist casting at lower temperature. The Harappan artefacts from Rangpur, Gujarat were also mostly made of copper and bronze, the latter containing 2-11 per cent tin. Bangles contained higher percentages of tin. Several samples contained nickel varying in percentage from 0.2 to as much as 5.9. Nickel was derived from the ore. (Lal, 1962-63) A Somnath axe (29.8 cm long) was made of bronze: copper alloyed with 12.8 per cent tin, 1.21 per cent lead and containing 2.57 per cent iron. Metallographic analysis of the Rosdi ring (Swarnakamal, 1980: 42) showed that this was carefully cast and subjected to mild working when the dendritic structure was broken.