Minerals and Metals in Ancient India v1.c14.s4.3

v1.c14.s4.3

Horace Beck was of the opinion that the surface of the steatite seals was painted with an alkali and then subjected to heat. A careful examination of the alkaline coat indicates the application of more than one coat of the liquid and even overlapping of brush marks. The chemical analysis has indicated that the covering film is made of the same material as the seal itself and appears to have been applied. After the application of the coating, the seal was baked to produce the white exterior while the core itself remained grey or greenish, and hardness was produced with the escape of water from the core. A closer examination of the seals reveals that engraving was done before the seal was fired. The chemical analysis of the white film covering the surface of the seals shows the following composition: