Minerals and Metals in Ancient India v1.c18.s4.t2.2

v1.c18.s4.t2.2

Metallographic examination showed that the copper sheet of Rājghāṭ had globular alternate banding of Cu-CuO eutectic. Annealing twins provided the evidence of heat-treatment having been done. Bronze coins had segregated Cu-rich Zone and Sn-rich grain boundary, proving that it was a cast structure. Very good coining and embossing were revealed in some Pre-Christian era Taxila coins which had glassy elongated slag streaks and fine equi-axed grains; these were evidently hot-worked, then cold-worked, and finally annealed. (Bhardwaj, 1979: 81)