History of Technology in India, Vol. I: From Antiquity to c. 1200 A.D. v1.c15.s7.8

v1.c15.s7.8

The Alkaline material used by the NBP potters, according to Hedge, was sājji māṭṭi. He produced the NBP in his laboratory using ground red ochre and sājji māṭṭi in clay (Hedge, 1975, 188). H.C. Bharadwaj, on the basis of his experiments, observes that “We may tentatively suggest that the black colour of the slip is materially on account of carbon and our experiments and observations do not substantiate the presence of magnetite or ferrous silicate.” (in Sinha, p.19)