Minerals and Metals in Ancient India v1.c18.s2.9

v1.c18.s2.9

The main component of the slag is fayalite which melts at 1170°C. The melting point of copper is 1083°C. Molten copper of high specific gravity 8.89 collected below the molten slag of the 4.0 sp. gr. The molten slag was evidently tapped on the edge of the terrace. When the furnace was cooled, the copper ingot was taken out by breaking its bottom. Hegde et al. (1985) may be right when they comment that “this simple furnace appears to have been continuously used in India over the millennia without little innovation”.