Minerals and Metals in Ancient India v1.c28.s8.t1.21

v1.c28.s8.t1.21

of each other, formed on each side of a common plane. Fine grain structure and the presence of twinned grains indicate that the object might have been first cold worked and then annealed at the recrystallisation temperature. Such an object (no. 8) is the beautifully modelled Ṛṣabhanāth of the Gupta Period (5th-6th century AD) from Akota; Swarnakamal pushes its date to a much later period probably because it contains 10.4 per cent zinc! Another object (No. 15), also from Akota-Tirīrthaka of Pārśvanātha (22 x 11 cm) — showed equiaxial grains along with a few twinning crystals, and also strain lines. Swarnakamal suggests (1980: 112) that this object was probably annealed to recrystallisation temperature, and then worked in cold or hot condition. This icon also contains appreciable amount of zinc 7.4 per cent and certified by the art scholars to belong to seventh century AD. Thus sophisticated casting, cold/hot working and annealing of bronze/brass icons used to be done in Akota and other places of Gujarat during seventh century AD; this is well before the Cālukya or Solaṅkī rule (AD 961-1222) which is claimed by Swarnakamal (1980: 172) to be the era introducing brass icons.